10 - EduSys · · 2011-08-22Experiment Water Transport in Plant Stems 16 6. Invent Potato Clock...

Class - X 3 Eduheal Foundation

CLASS ‐ X S. No. Category Topic Page No.

1. Syllabus Guide Line 04

2. Interactive Activity Periodic Table 07

3. Explore Colourful Investigation ! 12

4. Experiment Sinking and Floating Soda Cans 14

5. Experiment Water Transport in Plant Stems 16

6. Invent Potato Clock 19

7. Explore Chemistry Rapid Fire 21

8. Explore Magnetic Lines of Force 22

9. Invent Rubber Bands and Heat 26

10. Explore Shortcuts to Memorize : Elements 28

11. Activity Find Me ! Acids, Bases and Salts 29

12. Experiment The Magic of Copper Oxidation 31

13. Discover Blind Spot 33

14. Experiment Osmosis & Diffusion in an Egg 35

15. Experiment Survival of the Fittest 38

16. Explore Light House 40

17. Explore & Discover Why, What and How ? 43

18. Explore The Nervous System from A to Z 47

19. Discover Anti-Gravity Water 49

4 Class - X Eduheal Foundation

CLASS VIII Chemical Reactions & Equations Chemical Equations Types of chemical reactions. To observe following reactions: i. Burning of Mg ribbon ii. Reaction of Zn granules with dil HCl. iii. Formation of slaked lime by the reaction of CaO with water. iv. Heating crystals of FeSO 4 or CuSO 4 & Pb(NO 3 ) 2 v. Reaction of CuSO 4 solution and iron nails dipped in it vi. Reaction between Sodium Sulphate solution and Barium Chloride solution. vii. Oxidation of Cu to CuO. Chemical Reactions & Equations Corrosion, Rancidity i.To observe corrosion in different metals such as Iron, Aluminum, Copper, Silver etc. ii. To observe the rusting of Iron and conditions necessary for it. iii. To observe the changes in colour odour, etc. in cut fruits & vegetables. Acids, Bases & salts Chemical properties of acids & Bases Common properties of acids & bases i. Identification of Acids & bases using different indicators. ii. Passing CO 2 through Ca(OH) 2 solution. iii. Reaction of Metal carbonates and bicarbonates with acids. iv. Titration of acid with base using phenolphthalein. v. Preparation of HCl from NaCl and conc. H 2 SO 4 acid. Strength of Acids & Base solutions, Importance of pH value, more about salts, Chemicals from common salts i To test the pH value of different solutions and soil. ii Test pH of different salts To Find pH of the following samples by using pH paper /universal indicator –dil HCl, NaOH, Ethanoic acid, lemon juice, water, NaHCO 3 Life Process What are life processes, Nutrition, Respiration, Transportation Excretion i. To show that chlorophyll is essential for photosynthesis. ii. Testing presence of CO 2 in exhaled air. iii. To observe transpiration in plants. iv. To study the Excretion system of man with the help of a chart. To show that CO 2 is given out during respiration. To prepare a temporary mount leaf to show its stomata. To show that light is necessary for photosynthesis. Light – Reflection & Refraction Reflection of light, Spherical mirrors i. To study the images formed on both sides of shining spoon. To determine the focal length of concave mirror by obtaining the image of a distant object. Refraction of Light i. To study the images formed through spherical lenses of object kept at different distances. To determine the focal length of convex lens by obtaining the image of a distant object. To trace the path of a ray of light passing through glass slab. Human Eye & the colourful world Human eye, defects of vision and their correction, refraction of light through a prism. Dispersion of white light by glass prism, atmospheric refraction, scattering of light i. To study the parts of human eye with the help of model of human eye. ii. To identify the students in the class with eye defects and to suggest correction of vision with nutritional remedy.

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ii. To study the path of light passing through prism. iv. To study the dispersion of white light by glass prism. v. To study scattering of light in colloidal solution. Metals and Non metals Physical and chemical properties of metals, Reaction of metals and nonmetals, occurrence of metals, corrosion i. To Observe physical properties of metals such as Fe, Zn, and Cu and non metals such as graphite, Sulphur, Iodine. ii. To test conductivity through metals. iii. To test the chemical properties of metal oxides and non metal oxides. iv. To study the chemical reactions of metals with water, acids and solutions of other metal salts. v. To study reactivity series. vi. To investigate the conditions under which iron rusts. To observe action of Zn, Fe, Cu, Al on ZnSO 4 , FeSO 4 , CuSO 4 , Al 2 (SO 4 ) 3 . To prepare SO 2 gas and observe colour ,solubility in water, effect on litmus paper, action of K 2 Cr 2 O 7 Control and coordination Animals – Nervous system, coordination in plants, hormones and animals i. To observe reflex action in one’s body ii. To observe the functioning of taste buds. iii. To study parts of brain with the help of model/chart. iv. To study tropism in plants. v. To study Endocrine glands in man with the help of chart. Electricity Electric current and circuit, electric potential and potential difference circuit diagram, Ohm’s law i. To prepare a simple circuit ii .To study symbols of different components of a circuit. iii. To observe & learn to use instruments such as ammeter and voltmeter and learn to calculate their least counts. Electricity Factors on which the resistance of a conductor depends, resistance of a system of resistors, heating effect of electric current, electric power To determine the equivalent resistance of two resistors in series and in parallel. Magnetic effects of electric current Magnetic field and Magnetic lines, magnetic field current carrying conductor, force on a current carrying conductor in a magnetic field, electric motor i. To observe pattern formed by iron fillings around magnet. ii. To observe magnetic lines around a bar magnet with the help of a compass needle. iii. To observe magnetic field around a wire carrying current & change the direction of deflection with change of current direction. iv. To observe the magnetic field around current carrying loop. Magnetic effects of electric current Electro magnetic induction, electric generator, domestic electric circuit 1. To set up current in the coil circuit with the help of moving magnet Carbon and its compounds Bonding in carbonthe covalent bond, versatile nature of carbon i. To study the arrangement of atoms in allotrops of carbon (Ball and stick model). Chemical properties of carbon compounds, Important carbon compounds Ethanol and Ethanoic acid, soaps and detergents. i. To observe the burning of carbon compounds like camphor ii. To show cleansing action of soaps and detergent i. To study the following properties of acetic acid a) Odour b) Solubility in water c) Effect on litmus


d) Reaction with NaHCO 3 How do organism reproduce Modes of reproduction by single organism, variation in off springs, sexual reproduction i. To observe formation of mould on bread. ii. To observe different tissues in spirogyra filaments. iii. To observe leaf for budding in bryophylum iv. To study sexual reproduction in flowering plants & human beings with the help of chart paper. To study i. Binary fission in amoeba ii. Budding in yeast with the help of prepared slides. iii.. To study the amount of water absorbed by raisins. Heredity and Evolution Accumulation of variation during reproduction, heredity, evolution i. To study the works of Mendel ( 18221884) with the help of internet Heredity and Evolution Evolution, speciation, evolution and classification, evolution should not be equated with progress i. To study the works of Charles Darwin (18091882) with the help of internet. ii. To find out about homologous organs in different animal species Periodic classification of elements Attempts at classification of elements, Mendleef’s periodic table, Modern periodic table. i. To study the different classification made by different scientists. ii. To study Mendleef’s periodic table & Modern periodic table. Sources of energy Good source of energy, conventional source of energy, non conventional source of energy, environmental consequences i .List different forms of energy used by us. ii. To learn about different types of power plants. iii. To prepare and study the structure and working of solar cooker & heater. iv. To find out how energy sources affect environment. v. To study the factors that lead to Global Warming. Our Environment Ecosystem – what are its component, food chains and food webs, how do our activities affect the environment i. To collect the waste and categorize it into biodegradable and nonbiodegradable substances. ii. To design an aquarium and study it. iii. To find out the chemicals responsible for depletion of ozone layer with the help of relevant books, internet or newspaper. iv. To calculate the amount of waste generated in school and at home. Management of Natural Resources Need to manage our resources, Water for all, i. To find out about the international norms to regulate the emission of CO 2 . ii. To find out the extent of pollution of Ganga and Yamuna rivers with the help of internet and the measures being taken to clean it. iii. To check the pH of water supply of your house. Management of Natural Resources Coal and petroleum, an overview of natural resources management i. To find out about any two forest produce that are basis of an industry ii. To study the rainfall pattern in India from atlas. iii. To study water harvesting system. iv. To find out about Euro I and Euro II norms for emission from vehicles

* Kindly note that Syllabus guidelines are given for present class but 90% question paper of NISO will be based on previous class syllabus.


Periodic Table of the Elements Prashant is a student of class X. He was studying periodic

table with the interactive kit provided by Eduheal Foundation. He has square cards of elements having symbol, name, atomic number, atomic mass and valence shell electron of each element. While he was making the periodic table some of the square cards were spoiled by water. He managed to read the symbols on the cards. Being a student of his standard can you help him to complete his periodic table?

He gave correct answer to the following questions. Now, check if you can give the correct answer to the same questions.

Study the Periodic Table on page 8.

Q.1.Which of the following is placed at atomic number 28 position?

(a) Cs (b) Ni (c) La (d) In

Q.2.How many elements you have placed in noble gas category?

(a) 6 (b) 7 (c) 8 (d) 9

Q.3.Which of the following is placed before ‘In‛?

(a) Cd (b) Rn (c) Ra (d) Se

Q.4.Which element derives its symbol from the Latin word, aurum, which means ‘shining dawn‛?

(a) Aluminum (b) Americium (c) Gold (d) Silver

Interactive Activity : Periodic Table


Q.5.Which element best characterizes an organic compound?

(a) Oxygen (b) Carbon (c) Hydrogen (d) Nitrogen

Q.6.Where are the atoms with the largest atomic radius located?

(a) At the top of their group.

(b) In the middle of their group.

(c) At the bottom of their group.

(d) You cannot predict atomic radius by location within a group.

Fun with Periodic Table Use your periodic table to solve these puzzles. For each answer write down the name of the element and its symbol.

1. Which metal‛s symbol could be a nickname for Alan?

2. Find the superman element.

3. Find a metal named after Germany.

4. Find two more elements named after countries.

5. The famous scientist Albert_________ proved E=mc 2 .

6. Dmitri Mendeleev is the father of the periodic table. Can you find his element?

7. Which gas is used to kill germs in a swimming pool?


Put the symbols of these elements together to complete these messages

8. Salt and vinegar are my favourite Chromium Iodine Sulphur

Phosphorous Sulphur.

9. I like to Silicon Phosphorous my tea from a Copper

Phosphorous.

10. A Chromium Oxygen Tungsten is a type of blackbird.

11. If you are noisy, teacher can get Chromium Osmium Sulphur.

12. It‛s nice to get a Potassium Iodine Sulphur Sulphur on the Lithium Phosphorous Sulphur.

10. NITROGEN FACTS 1. Nitrogen is odourless, tasteless, and colourless.

2. Nitrogen gas (N 2 ) makes up 78.1% of the volume of the Earth‛s air.

3. Nitrogen is a non-metal.

4. Nitrogen gas is relatively inert, but soil bacteria can ‘fix‛ nitrogen into a form that plants and animals can use to make amino acids and proteins.

5. The French chemist Antoine Laurent Lavoisier named nitrogen azote, meaning without life.

6. Nitrogen was sometimes referred to as ‘burnt‛ or ‘dephlogisticated‛ air. One of its oxide is used as laughing gas.


7. Nitrogen compounds are found in foods, fertilizers, poisons and explosives.

8. Nitrogen is responsible for the orange-red, blue-green, blue- violet and deep violet colours of the dawn.

9. One way to prepare nitrogen gas is by liquefaction and fractional distillation from the atmosphere.

10 Oxygen Facts 1. Animals and plants require oxygen for respiration.

2. Oxygen gas is colourless, odourless, and tasteless.

3. Liquid and solid oxygen are pale blue.

4. Oxygen is a non-metal.

5. Oxygen gas normally is the divalent molecule O 2 . Ozone, O 3 , is another form of pure oxygen.

6. Oxygen supports combustion.

7. Oxygen is paramagnetic.

8. Approximately 2/3 of the mass of the human body is oxygen.

9. Excited oxygen is responsible for the bright red and yellow- green colours of the dawn.

10. Oxygen was the atomic weight standard for the other elements until 1961 when it was replaced by carbon 12.

Make a phrase of your own using the elements. _________________________________________________ _________________________________________________ _________________________________________________

Now you are nearly finished, which element thanks you by saying


Catching criminals with colour Hey ! Do you want to be a forensic scientist ?

Follow these instructions to create your own chromatography experiment and learn about how ink can help forensic scientists to catch criminals.

Forensic scientists extract the ink from the writings so that it can be analysed. The extracted ink can then be compared with ink from the pens of the suspects.

What you need To do this experiment you will need the following items:

filter paper scissors a jar ink pens and markers two paper clips water.

What to do

1 Cut a filter paper into strips about 2 cm wide. The length depend on the size of the jar you hang them in.

Colourful Investigation !

Catch criminals with ink? It‛s easy!


2 Draw a small circle 1 cm from the bottom of the paper with different black markers or ink pens. 3 Fill a clean jar with about 1 cm of water and carefully place the paper into the jar making sure that the bottom of the paper is in the water. The circle must be ABOVE the water level. Use paper clips to hold the paper upright in the jar. Watch the water rise up the paper. 4 After a few minutes remove the paper from the jar. Notice how different colours in the ink travel up the paper at different speeds. 5 Now try some different colour pens and markers. Can you see any differences? 6 Did you have any pens for which the ink did not separate? If so, repeat the experiment using methylated spirits such as after shave lotion instead of water in the jar. Try out a variety of pens. Can you see any differences?

What’s Going On : The method used to compare inks is called chromatography. It

involves separating the ink in each of the pens. As the solvent (water) rises up the paper, the different colours of the ink separate.

Ask your family members to play your suspects. Ask them to use specific pens for the job and see if you can figure out which ink comes from which pen and nab your suspect!


Imagine a hot summer day. You are at a picnic and go to the ice chest where the sodas are staying nice and cool. Which cans are floating in the ice water, and which have sunk to the bottom?

You will need: several unopened cans of regular soda of

different varieties several unopened cans of diet soda of

different varieties a large aquarium or sink

You will do: Fill the aquarium or sink almost to the top with water. Place a

can of regular soda into the water. Make sure that no air bubbles are trapped under the can when you place it in the water. Does it sink or float? Repeat the experiment with a can of diet soda. Does it sink or float?

Why does one can sink, and the other can float? The cans of soda have exactly the same volume, or size. But

their density differs due to what is dissolved in the soda. Regular soda contains sugar as a sweetener. If you look at the nutrition facts on a can of regular soda, you will notice that it contains a lot of sugar. In some cases a 300 grams can of regular soda will contain over 40 grams of sugar. Diet sodas, on the other hand, use artificial sweeteners such as aspartame. These artificial sweeteners may be hundreds of times sweeter than sugar, which means that less than a few grams of artificial sweetener is used

Sinking and Floating Soda Cans


in a can of diet soda. The difference in the amount of dissolved sweeteners leads to a difference in density. Cans of regular soda tend to be more dense than water, so they sink. Cans of diet soda are usually less dense than water, so they float.

Explore Are there any varieties of regular soda that will float? Are

there any varieties of diet soda that sink? Can you think other factors that might influence which sodas float or sink?

Students of physics are frequently told Of experiments performed by great physicists of old Like Boyles and Charles — but greatest of these Was the Principle discovered by Archimedes. The Sicilian King, Archimedes was told, Ordered a crown from a large lump of gold, And though the weight of the gold was completely correct, The goldsmith‛s eye made the King suspect That he had made up the weight with some cheaper metal And stolen some gold, that his debts he might settle. His problem was then of outstanding immensity As he had no idea, whatsoever, of density. Climbing into a bath he received a surprise When he noticed the water beginning to rise. He suddenly snapped, and let out a scream, As he realised, with joy, his long-wished-for dream. He found the upthrust, produced on a body‛s base*, To be equal in weight to the water displaced, And soon volumes and weights would make it quite plain What various metals the crown could contain, And so he could easily show to his Royalty The absolute proof of the goldsmith‛s disloyalty. Leaping out of the bath at remarkable rate, He made for the palace by doorway and gate — But the men in the street were completely confounded To see a naked man shout “Eureka! I‛ve found it!” * Is this the only error? The upthrust is not on the base, but at the Centre of Pressure.

Eureka !


As water evaporates from the leaves of a plant, more water is drawn up by osmosis from the tissues below to replace it. The replacement of water lost through transpiration is possible because water molecules have polar covalent bonds. This causes one end of the molecule to have a slightly positive charge and the other end to have a negative charge. Because of this, the water molecules act like “small magnets”. The positive end of one water molecule sticks to the negative end of another in a long chain that is pulled upward against the force of gravity.

When enclosed in a narrow tube, such as the transport vessels of a plant, water molecules can withstand a large force without being pulled apart.

Materials Needed: 1 Celery stalk with leaves intact 5 Scale

2 400-mL beaker 6 Distilled water

3 Glass bowl 7 Red food colouring

4 blade 8 Stirring rod

Water Transport in Plant Stems Mesophyll cells

Xylem vessel

Air space

Water molecule Guard cell Stoma


Procedure: 1 Fill the beaker with 100 mL of distilled water. Add drops of red food colouring, stir with the stirring rod, until the water is a dark red colour. Set this aside.

2 Put some distilled water in the glass bowl. While holding the bottom end of the celery stalk under water, cut off the bottom two centimetres of the celery stalk.

3 Quickly place the freshly cut celery stalk upright in the beaker of coloured water. Record the beginning time on your DATA TABLE.

4 Allow the celery to remain in the food colouring until the colour is visible in the upper stem and leaves. Record the ending time on your DATA TABLE, and remove from the beaker of food colouring.

5 Measure the length the red colour traveled up the celery stalk in centimetres. Record on your DATA TABLE.

Data Table: Beginning time: ___________ Ending time: _____________

Length food colour travelled up stalk __________ cm

Calculations: 6 Calculate the number of minutes it took for the colouring to reach the top. Time for colour to reach the top of stalk = _________ minutes


7 Calculate the rate of travel of the food colouring up the celery stalk in centimetres per minute

Rate of Travel = length of celery stalk(cm)

time for colour to reach top of stalk(min)

Rate of travel = _________ cm / min

Now try to find out answers of these Questions: 1. What type of tissue moves water upward in a plant stem?

____________________________________________

2. Name and explain two properties of water that enable it to move upward against gravity in a stem.

____________________________________________

____________________________________________

3. What is transpiration and where does it occur in plants?

____________________________________________

____________________________________________

4. How does transpiration help the upward movement of water?

____________________________________________

____________________________________________

____________________________________________


Potato Battery You have seen and even used a variety of batteries. But can you ever imagine that potato – the most common vegetable found in kitchens, can be used as battery ? Come lets do and find...

A potato battery is a type of electrochemical cell. An electrochemical cell converts chemical energy into electrical energy. In the potato battery, there is a transfer of electrons between the zinc coating the galvanized nail that will be inserted into the potato and the copper wire that will be inserted into another part of the potato. The potato conducts electricity, yet keeps the zinc ions and copper ions separate, so that the electrons in the copper wire are forced to move (generate current). The power is not enough to shock you, but the potato can run a small digital clock or light an LED (light emitting diode)

You will need: 2 potatoes

2 short lengths of copper wire

2 galvanized nails (not all nails are galvanized or zinc-coated)

3 alligator clip wire units (alligator clips connected to each other with wire, available at any electrical shop

1 low-voltage LED clock (type that takes a 1-2 volt button battery)

Potato Clock

LED


computer fan

How to Make a Potato Clock Here what you need to do is to turn the potato into a battery and get it to work the clock: 1 Insert a galvanized nail into each potato. 2 Insert a short piece of copper wire into each potato. Put the wire as far as possible from the nail. 3 Use an alligator clip to connect the copper wire of one potato to the positive (+) terminal of the clock‛s battery compartment. 4 Use another alligator clip to connect the nail in the other potato to the negative (-) terminal in the clock‛s battery compartment. 5 Use the third alligator clip to connect the nail in potato one to the copper wire in potato two. 6 Set your clock

Potato Battery ‐ More Fun Things to Try Let your imagination run with this idea. There are variations on the potato clock and other things you can try. See what else your potato battery can power. It

should be able to run a computer fan. Can it light a light bulb?

Try substituting copper coins (if you have them!) for the copper wire.

Potatoes are not the only foods that can act as electrochemical cells. Experiment with lemons, bananas, pickles, or cola as a power source.


Following are some very simple terminology/defination. You can use this as a rapid fire quiz to play in your class. 1. The solid that dissolves in a liquid: 2. The liquid that does the dissolving: 3. The mixture of dissolved solid and liquid: 4. A material that has a fixed shape: 5. A material that has a fixed volume but not a fixed shape: 6. A material that does not have a fixed volume or shape: 7. When a solid disappears into a liquid: 8. Two or more different materials together: 9. To make jelly dissolve more quickly you make the water: 10. Method used to separate small pieces of solid from a liquid: 11. When a liquid become a gas: 12. When a gas becomes a liquid: 13. The temperature that a liquid becomes a gas: 14. When a solid becomes a liquid: 15. Freezing point of water: 16. Boiling point of water: 17. To make jelly dissolve more quickly you make it into ...: 18. When salt water boils away the salt is …: 19. A material that contains only one type of particle: 20. When cake mix is heated it goes solid. This change is …:

search for answers

Chemistry Rapid Fire


Iron filings will line up parallel to a magnetic field, making the pattern of the field visible. Since the filings are trapped in a bottle, they don‛t make a mess.

You will Need: A plastic bottle, 1/2 litre size.

A plastic test tube that fits into the mouth of the bottle and is about 75% as long as the bottle is tall.

A cow magnet or other cylindrical magnet that fits into the plastic tube.

Masking tape.

Iron filings

Here’s How Fill the Plastic bottle about one-fifth full of iron filings. Wrap the top of the test tube with masking tape so that the tube fits snugly into the mouth of the bottle, plugging the opening completely. After you put the iron filings into the bottle, jam the tube into the mouth of the bottle.

Slide the cylindrical magnet into the test tube and put the bottle cap back on. Turn the bottle on its side and rotate it.

Magnetic Lines of Force Iron filings will trace out the lines of a

magnetic field in three dimensions


Watch what happens to the iron filings. They will form a three- dimensional pattern that traces out the magnetic field of the magnet.

Pay attention to what happens at the end of the magnet. Here, the iron filings stand out like a punk haircut. Shake the magnet out of the tube, and watch the filings collapse.

What’s going On? Each atom in a piece of iron is a magnet, with a north pole and a south pole. Most pieces of iron are not magnetic since the atomic magnets all point in different directions.

When you bring a magnet near a piece of iron, the iron-atom magnets line up with the applied magnetic field. The north poles of the iron atoms all point in the same direction. Because the iron atoms line up, the piece of iron becomes a magnet and is attracted to the original magnet.

In a rod-shaped piece of iron, the atoms will tend to line up so that all the north poles face one end of the rod and all the south poles face the other end. Since iron filings are rod-shaped, the atoms line up pointing along the length of the rod, and the rods line up parallel to the direction of the applied magnetic field. The


field of a cylindrical magnet comes out of the end of the magnet and then loops around next to the side. The iron filings stick out like a crew cut on the ends of the magnet but lie flat on the sides.

Because the iron filings become magnets themselves, their presence slightly changes the shape of the magnetic field. Even so, this experiment gives an indication of the shape of the magnetic field in three dimensions.

Etcetera If you use a plastic bottle and seal it well by jamming the test tube into its mouth, the sides of the bottle will begin to collapse inward after a few hours - particularly if the inside of the bottle is damp. This happens because the iron filings are rusting. As the iron rusts, it combines with oxygen and removes it from the air trapped in the bottle. To prevent the bottle‛s collapse, simply punch a small hole in the plastic with a pin.

Cow magnets are strong, permanent magnets made out of alnico, an iron alloy containing aluminium, nickel, and cobalt. Ranchers feed these magnets to their cows. The magnet settles in the cow‛s first stomach. When the cow eats bits of steel or iron, the magnet attracts the metal bits and holds them in the first stomach. If the sharp pieces of metal were to pass through the cow, the animal would suffer what ranchers call “hardware disease.”

Answers of Chemistry Rapid Fire

1. Solute 2. Solvent 3. Solution 4. Solid 5. Liquid 6. Gas 7. Dissolving 8. Mixture 9. Hotter 10. Filtration 11. Evaporation 12. Condensation 13. Boiling point 14. Melting 15. 0ºC 16. 100ºC 17. Smaller pieces 18. Left behind 19. Pure 20. Irreversible


Everyone has used rubber bands, but few people have taken the time to observe the less obvious properties of these everyday objects. In this activity you will examine the thermal properties of rubber, that is, the behaviour of rubber as it relates to heat, a form of energy.

In the first experiment you will attempt to detect heat flow into or out of a rubber band. To do this, you need a rather sensitive heat detector. Fortunately, you have such a detector with you at all times. Surely, you‛ve felt the heat of a flame or the cold of an ice cube. Therefore, you know that your skin is sensitive to heat flow. In this experiment, you will detect heat flow using some of your most sensitive skin, that on your forehead or on your lips. 1 Place your thumbs through the heavy rubber band, one on each end. Without stretching the band, hold it to your forehead or lip. Does the band feel cool or warm or about the same as your skin? Repeat the test several times until you are sure of the result. 2 Move the rubber band slightly away from your face, so it is not touching your skin. Quickly stretch the band about as far as you can and, holding it in the stretched position, touch it again to your forehead or lip. Does it feel warmer or cooler or about the same as it did when it was relaxed? 3 Move the stretched rubber band away from your face. Quickly it relax to its original size and again hold it to your skin. Does it feel warm or cool? 4 Repeat the stretching and testing, and relaxing and testing several times until you are sure of the results.

An object feels cool or cold to you when heat flows from your

Rubber Bands and Heat


skin to the object. Conversely, an object feels warm or hot when heat flows from the object into your skin. If the stretched rubber band feels cool, then it absorbs heat from your skin. If it feels warm, then it gives off heat to your skin. If the band feels neither warm nor cool, then there is no detectable heat flow. These three cases can be represented as follows:

Case 1. Relaxed Band + Heat Stretched Band

Case 2. Relaxed Band Stretched Band + Heat

Case 3. Relaxed Band Stretched Band (No Heat)

Which of these three cases best describes what you observed?

There is another way to test which of the three statements is correct. We can see what happens to the length of a rubber band if we heat or cool it. 1 Hang one end of the rubber band from the wall or ceiling and suspend a weight from the other end of the rubber band. (What you use for a weight will depend on what is available. The weight should be heavy enough to stretch the rubber band, but not so heavy that it is likely to break the band. For example, hang the band over a door knob and suspend a hammer from the band.) 2 Heat the rubber band with a hair dryer. Start the dryer and, when it has warmed up, turn its heat on the stretched rubber band. Does the stretched rubber band become longer or shorter when it is heated?

Does this observation agree with what you found in the first part of the experiment? Doing an experiment several ways and checking for agreement in the results is an important strategy in science.

When rubber is heated it behaves differently than most familiar


materials. Most materials expand when they are heated. Consider the liquid in a thermometer. The thermometer works because the liquid expands when its temperature increases. Similarly, a wire made of metal, such as copper, becomes longer as it gets hotter. The expansion of metals with increasing temperature is the principle behind the functioning of home thermostats and of jumping discs.

Whether a material expands or contracts when it is heated can be ascribed to a property of the material called its entropy. The entropy of a material is a measure of the orderliness of the molecules that make up the material. When the molecules are arranged in an ordered fashion, the entropy of the material is low. When the molecules are in a disordered arrangement, the entropy is high. (An ordered arrangement can be thought of as coins in a wrapper, while a disordered one as coins in a tray.) When a material is heated, its entropy increases because the orderliness of its molecules decreases. This occurs because as a material is heated, its molecules move about more energetically. In materials made up of small, compact molecules, e.g., the liquid in a thermometer, as the molecules move about more, they push their neighbouring molecules away. Rubber, on the other hand, contains very large, threadlike molecules. When rubber is heated, the sections of the molecules move about more vigorously. In order for one part of the molecule to move more vigorously as it is heated, it must pull its neighboring parts closer. To visualize this, think of a molecule of the stretched rubber band as a piece of string laid out straight on a table. Heating the stretched rubber band causes segments of the molecules to move more vigorously, which can be represented by wiggling the middle of the string back and forth. As the middle of the string moves, the ends of the string get closer together. In a similar fashion, the molecules of rubber become shorter as the rubber is heated, causing the stretched rubber band to contract.


Here is memorisation mantra to remember the symbols for the elements. Come on, fast, memorise them. Silver Ag : If a person who is expecting a gift of a gold

necklace receives a silver one. He might say, “Ag, I didn‛t want silver!”

Gold Au : “A you, I want that gold necklace!” Said with “A you” sound like Au.

Aluminium Al :Al cans are made from aluminum. Bromine Br: That brother of mine, Bro of mine! Calcium Ca: “Caws give milk!” Pronounced with an accent to make

cows sound like it‛s spelled with an A. Chlorine Cl: “You Clean with chlorine!” Fluorine F: You need to Floss after using fluorine! Iron-Fe: “Fe Fi, Fo, Fum, I‛m an iron man!” Helium He: If you breathe in helium, you will laugh! He, He, He! Mercury, Hg: Greek mythology Hg stands for Helmet guy! Potassium K: You will get Kicked out of school for the double

nasty! You can‛t do the first three letters and cannot say the next three!

Sodium, Na: “Na I don‛t want any sodium!” Nickel, Ni: “Nilesh owes me a nickel!” Oxygen O: “Open your mouth wide to take in oxygen!” Lead - Pb: Pencil broke! Silicon Si: Silly cone! Tin, - Sn: A tin roof gets hot in the Sun. Manganese: (Mn)Take first three letters Man. Magnesium: (Mg)Take first three letters Mag.

Shortcuts to Memorize : Elements


1. I am pure water. When heated my pH (increases, decreases), because more of my water molecules dissociate.

2. I am a 0.020 M solution of weak acid. If I only dissociate to the extent of 1.50%, what is the value of my K a ?

3. I am a 0.20 M solution of hydrocyanic acid, HCN, with a K a of 4.93 x 10 –10 . What is my pH?

4. I am a buffer made from 0.10 M acetic acid and 0.15 M sodium acetate. If the K a for acetic acid is 1.77 x 10 –5 , what is my pH?

5. I am a substance who turns blue litmus red, neutralizes bases, and tastes sour. What am I?

6. I am a species who turns red litmus blue, neutralizes acids, and tastes bitter. What am I?

7. I am a 0.020 M solution of a weak acid, who dissociates to the extent of 3.5%. What is the value of my K a ?

8. I am a Bronsted-Lowry acid. Therefore, I am a ___________ donor.

9. I am a Bronsted-Lowry base. As a result, I am a proton ______________.

10. I am a bicarbonate ion, HCO 3 – . Because I can both donate and

accept a proton under certain conditions, I am called a(n) ______________________ species.

True and False 11. Water is neither an acid nor a base in the Arrhenius system. 12. The molarity of water in pure water and in most aqueous

solutions is approximately 55.6 M.

Find Me ! Acids, Bases and Salts


13. The reaction of an acid with a base to produce a salt and water is an endothermic reaction.

14. The larger the value of K a , the stronger the acid. 15. The stronger an acid, the stronger its conjugate base. 16. The strongest acid that can exist in aqueous solutions is

perchloric acid. 17. The strongest base that can exist in aqueous solutions is the

OH – ion. 18. A solution with a pH of 13 would be acidic. 19. A solution with a pOH of 12 would be basic. 20. The hydrogen ion concentration in a solution with a pH of 5.65

is ten times that of one with a pH of 6.65. Choose the correct word 21. A(n) (Bronsted-Lowry, Lewis, Arrhenius) acid is an electron

pair acceptor. 22. CH 3 COOH, acetic acid, is a (weak, strong) acid. 23. C 2 H 5 OH is a(n) (acid, base, salt, alcohol). 24. The greater the degree of dissociation, the (stronger, weaker)

the acid. 25. Acids, bases, and salts are (electrolytes, none electrolytes). 26. Neutralization is a (fast, slow) reaction. 27. The (Arrhenius, Bronsted-Lowry, Lewis, Usanovich) theory is

the most conservative acid-base theory and also the oldest. 28. The aquated proton is often called the (hydronium, hydroxide)

ion. 29. CH 3 COOH is a(n) (acid, base, salt). 30. NH 4 Cl is a(n) (acid, base, salt).

search for answers


Have you ever thought how the iron grills of your window, gate or the pipes develop brownish flaky surfaces? This brownish-flaky surface is caused due to rusting. Oxidation causes many metals to rust. Similarly, a natural green finish oppears on copper through its oxidation, which is called verdigris. This green finish on the copper acts as guard against acids and oils that may eat away at the copper metal.

In this experiment you will oxidise copper using ammonia. This process will create a verdigris finish on your copper object. You will Need: Copper object such as coins, a copper utensil or copper pieces Ammonia that you use in your home Copper-carbonate solution (- ask your science teacher for this

solution) Water bottle that has a sprayer Measuring cup Brass cleaner Large spoon Plastic bucket Small paintbrush Tissue papers Newspapers Paper Pencil

Here’s how: Complete the following steps to prepare your environment and materials: 1 Find a well ventilated room that contains floor space. Place newspaper across the floor that will cover the area of a dinner table. 2 The copper object should be thoroughly cleaned of any varnish. Therefore, use the tissue paper and add a small amount of brass

“The Magic of Copper Oxidation”


cleaner to the copper object. Remove varnish from your copper object by letting the brass cleaner dry and then wiping it off with a new paper tissue. 3 The copper will be oxidized using a mixture of ammonia and copper carbonate. Create this mixture by placing one cup of ammonia and 0.25 cup of copper carbonate solution into the plastic bucket. Use the large spoon to mix the solution. It is critical to be in a well ventilated area so that you do not ingest any of the dangerous fumes from the solution. Get‐Set‐Go‐ 1 You are now going to coat your copper object with the ammonia and copper carbonate solution mixture. Dip the small paintbrush into the ammonia and copper carbonate solution mixture. Paint only the outside of the copper object using the solution. (Do not paint the inside of your copper object so that you can compare it to the copper oxidation of the outside of your copper object.) 2 Let your copper object sit until it dries. 3 Repeat Step #1 and Step #2 six more times. The more times you paint your copper object, the deeper the copper object is oxidized. What colour has the outside of the copper object turned to? What colour is the inside of your copper object? Record your findings. 4 Use the water bottle to lightly spray water on your copper object. What was the effect of spraying water on the copper object? Record your findings. Summary of Results: The ammonia and copper carbonate solution mixture reacts with the air and water which causes copper oxidization. The copper oxidizes into a green colour known as “Verdigris”. Spraying water on the copper object causes the oxidizing solution to become less concentrated thus giving a blue colour.


The eye‛s retina receives and reacts to incoming light and sends signals to the brain, allowing you to see. There is, however, a part of the retina that doesn‛t give you visual information. This is your eye‛s blind spot.

You will Need: One 3 X 5 inch (8 x 13 cm) card or other stiff paper

A metrestick

Here’s How Mark a dot and a cross on a card as shown.

Hold the card at eye level about an arm‛s length away. Make sure that the cross is on the right.

Close your right eye and look directly at the cross with your left eye. Notice that you can also see the dot. Focus on the cross but be aware of the dot as you slowly bring the card toward your face. The dot will disappear, and then reappear, as you bring the card toward your face.

Blind Spot


Now close your left eye and look directly at the dot with your right eye. This time the cross will disappear and reappear as you bring the card slowly toward your face.

Try the activity again, this time rotating the card so that the dot and cross are not directly across from each other. Are the results the same?

What’s going on? The optic nerve carries messages from your eye to your brain. This bundle of nerve fibres passes through one spot on the light sensitive lining, or retina, of your eye. In this spot, your eye‛s retina has no light receptors. When you hold the card so that the light from the dot falls on this spot, you cannot see the dot.

As a variation on this blind spot activity, draw a straight line across the card, from one edge to the other, through the centre of the cross and the dot. Notice that when the dot disappears, the line appears to be continuous, without a gap where the dot used to be. Your brain automatically “fills in” the blind spot with a simple extrapolation of the image surrounding the blind spot. This is why you do not notice the blind spot in your day-to-day observations of the world.

Answers of Find me ! Acids Bases & Salt

(1) decreases (2) 4.5 x 10 –6 (3) 5.00 (4) 4.92 (5) acid (6) base (7) 2.5 x 10 –5 (8) proton (9) acceptor (1O) amphiprotic(11) true (12) true (13)false (14) true (15) false (16) alse (17) true (18) false (19) false (20) true (21) Lewis (22) weak (23) alcohol (24) stronger (25) electrolytes (26) fast (27) Arrhenius (28) hydronium (29) acid (30) salt


You know the day-to-day use of eggs in preparing different recipes, having as boiled eggs, omlettes etc. But have you ever thought that they can be used to determine any scientific phenomenon? Come lets do & see. Here you will use a fresh hen‛s egg to determine what happens during osmosis & diffusion across membranes.

Materials Required: 1-2 fresh hen eggs in their shells masking tape & marker distilled water clear sugar syrup vinegar clear jar with lid tongs electronic balance tissue paper paper pencil

Here’s How: Day 1

1 Label the jar with the word “vinegar”. 2 Weigh the egg with the electronic balance & record in the

data table. 3 Carefully place the raw egg into the jar & cover the egg with

vinegar. 4 Loosely re-cap the jar & allow the jar to sit for 24 to 48

hours until the outer calcium shell is removed. Day 2 1 Open the jar & pour off the vinegar.

Osmosis & Diffusion in an Egg


2 Use tongs to carefully remove the egg to a tissue paper (or blotting paper) & pat it dry.

3 Record the size & appearance of your egg in your data table. 4 Weigh the egg on an electronic balance & record. 5 Clean and re-label the jar with the word “distilled water”. 6 Carefully place the egg into the jar & cover the egg with

distilled water. 7 Loosely re-cap the jar & allow it to sit for 24 hours.

Day 3 1 Open the jar & discard the distilled water. 2 Use tongs to carefully remove the egg to a tissue paper & pat

it dry. 3 Record the size & appearance of your egg in your data table. 4 Weigh the egg on an electronic balance & record. 5 Clean and re-label the jar with the word “syrup”. 6 Carefully place the egg into the jar & cover the egg with clear

syrup. 7 Loosely re-cap the jar & allow it to sit for 24 hours.

Day 4 1 Open the jar & pour off the syrup. 2 Use tongs to very carefully remove the egg & rinse off the

excess syrup under slow running water. 3 Pat the egg dry on a tissue paper. 4 Record the size & appearance of your egg in your data table. 5 Weigh the egg on an electronic balance & record. 6 Clean up your work area & put away all lab equipment.


Data: RESULTS OF DIFFUSION

Original Mass Final Mass Appearance of Egg

VINEGAR

WATER

SYRUP

Questions & Conclusion: 1. Vinegar is made of acetic acid & water. Explain how it was able

to remove the calcium shell. 2. (a) What happened to the size of the egg after remaining in

vinegar? (b) Was there more or less liquid left in the jar? (c) Did water move into or out of the egg? Why?

3. (a) What happened to the size of the egg after remaining in distilled water?

(b) Was there more or less liquid left in the jar? (c) Did water move into or out of the egg? Why?

4. (a) What happened to the size of the egg after remaining in syrup?

(b) Was there more or less liquid left in the jar? (c) Did water move into or out of the egg? Why?

5. Was the egg larger after remaining in water or vinegar? Why? 6. Why are fresh vegetables sprinkled with water at markets? 7. Roads are sometimes salted to melt ice. What does this salting

do to the plants along roadsides & why?


Within a population, organisms vary. Charles Darwin stated that in the struggle for existence, those variant organisms that have favourable variations are “better adapted” to their environment and will survive and reproduce in greater numbers. Favourable variations may mean that they are faster, or stronger, or able to eat different types of food, or better camouflaged to avoid predators. In this experiment you will simulate the effect of predation by a hawk on a large population of assorted mice. Your population of mice will consist of black, white, and speckled mice. You will represent the hawk. Objectives: to simulate the effect of hawk predation on the appearance of

mice to simulate the natural selection of traits Materials: large sheet of newspaper 4 hawks (make a group of four or you alone can do by repeating

the process 4 times) 30 white mice (paper squares) 1 petri dish 30 speckled mice (paper squares) 30 black mice (paper squares) Here’s How: Open your sheet of newspaper and place it on the experimental table. This will serve as the environment for your mice. l Place the petridish on the other side of the experimental table. This will be the nest.

Survival of the Fittest


l Select one person from your group to act as a hawk. This person should stand by the nest. l Spread the mice on their environment evenly. l The hawk now swoops over and has 1 minute to pick up as many mice as possible. The hawk may only pick up one mouse at a time, and must place it in their nest (a petridish) before flying back to pick up another. The goal is to pick up as many mice as possible in the time period. l When the time is up record the number of mice left in the environment in the data table below. l Repeat this procedure for each person in the lab group or do yourself 4 times. l After all the data is collected, construct a bar graph. Be sure to label the graph and its axis. Data:

Whitemice Speckled mice Blackmice Hawk #1 Hawk #2 Hawk #3 Hawk #4 Total

Conclusion: Write a paragraph describing; the purpose of the experiment. what you thought the results would be? what the results were (discussing numbers from data)? how the mouse population and hawk population may change over

time from natural selection?


Have you ever tried to find out how is the light of a lighthouse magnified so that it can be seen many miles out at sea? Let‛s explore how it happens?

A lighthouse light is a concentrated beam, focused by special lenses. Because of its highly increased intensity, this beam of light can travel a very long distance.

The design of the lighthouse light as we know it today, originated at the beginning of the 18th Century. The French physicist Augustin Fresnel had deduced that light was pure energy that traveled in waves, and he then spent his life developing lenses and reflectors that could capture and concentrate light. The first lighthouse optics that he designed combined highly polished prisms with an array of lenses that captured light and concentrated it back into a main beam. The design was concentric in arrangement, funneling the light into a beam that was many times brighter than its source. This light could be seen for more than 20 miles. Fresnel‛s design of concentric glass rings to concentrate light is still used today in the production of automobile headlights, traffic signals and projectors. Many of today‛s lighthouses have a system of rotating lenses, and the newer ones flash off and on as a way of conserving energy.

The earliest lighthouses were simply bonfires built on hilltops to guide ships. The light from a bonfire could not have been very bright or traveled vary far. No doubt it was better than other

Light House


lights but still improvements were to be done.

Then in 1822 Augustine Fresnel invented a lens. A fresnel lens looks like a giant glass beehive, with a light at the center. The lens could be (and usually is) as tall as twelve feet, with concentric rings of glass prisms above and below to bend the light into a narrow beam. At the center the lens was shaped like a magnifying glass, so the concentrated beam was even more powerful. Tests showed that while an open flame lost nearly 97% of its light, and a flame with reflectors behind it still lost 83% of its light, the fresnel lens was able to capture all but 17% of its light. Because of its amazing efficiency, a fresnel lens could easily throw its light 20 or more miles to the horizon. Because of the improved range, it became necessary to build taller light houses to enable the full range to be achieved - hence overcome the curvature of the earth.

The above is an example of a plain first-order (non-flashing) lens. This one has an unusual green colour. Orders of lenses were developed. There were seven types, the first three orders and largest were for seacoast lights, while orders four through six were smaller, for harbour or bay lights. There was also a 3.5 order lens.

Why did the chicken cross the road? Aristotle: It is the nature of chickens to cross roads. Isaac Newton: Chickens at rest tend to stay at rest, chickens in motion tend to cross roads. Albert Einstein: Whether the chicken crossed the road or the road moved beneath the chicken depends on your frame of reference. Werner Heisenberg: We are not sure which side of the road the chicken was on, but it was moving very fast. Wolfgang Pauli: There already was a chicken on this side of the road.


Fresnel Lens If you have ever looked at the lens of a magnifying glass, you know that it is thick in the middle and tapers down to nothing at the edges. In other words, it is shaped like a lentil, which is where the word lens comes from.

The thin piece of plastic you are using is called a Fresnel lens. It is flat on one side and ridged on the other. Fresnel lenses we first used in the 1800 as the lens that focuses the beam in lighthouse lamps. Plastic Fresnel lenses are used as magnifiers when a thin, light lens is needed. The quality of the image is not nearly as good as that from a continuous glass lens.

The basic idea behind a Fresnel lens is simple. Imagine taking a plastic magnifying glass lens and slicing it into a hundred concentric rings (like the rings of a tree). Each ring is slightly thinner than the next and focuses the light toward the center. Now take each ring, modify it so that it‛s flat on one side, and make it the same thickness as the others. To retain the rings‛ ability to focus the light toward the center, the angle of each ring‛s angled face will be different. Now if you stack all the rings back together, you have a Fresnel lens. You can make the lens extremely large if you like. Large Fresnel lenses are often used as solar concentrators.


Q Why does ultraviolet light cause colour to fade?

It is all about the chemical makeup of an object. The technical term for colour fading is photodegradation. There are light absorbing colour bodies called chromophores that are present in dyes. The colour(s) we see are based upon these chemical bonds and the amount of light that is absorbed in a particular wavelength.

Ultraviolet rays can break down the chemical bonds and thus fade the colour(s) in an object - it is a bleaching effect. Some objects may be more prone to fading, such as dyed textiles and watercolours. Other objects may reflect the light more, which makes them less prone to fade.

Why, What and How ?

What is ultraviolet light?

Of the three types of energy contained in sunlight-ultraviolet radiation, visible light, and infrared radiation–ultraviolet (UV) can be the most dangerous.


Q What causes the noise when you crack a joint?

Escaping gases, movement and rough surfaces.

Your joints can make a variety of sounds: popping, cracking, grinding, and snapping. The joints that “crack” are the knuckles, knees, ankles, back, and neck. There are different reasons why these joints “sound off”.

Escaping gases: Scientists explain that synovial fluid present in your joints acts as a lubricant. The fluid contains the gases oxygen, nitrogen, and carbon dioxide. When you pop or crack a joint, you stretch the joint capsule. Gas is rapidly released, which forms bubbles. In order to crack the same knuckle again, you have to wait until the gases return to the synovial fluid.

Movement of joints, tendons and ligaments: When a joint moves, the tendon‛s position changes and moves slightly out of

An Osteoarthritic Joint. With osteoarthritis, the cartilage becomes worn away. Spurs grow out from the edge of the bone, and synovial fluid increases. Altogether, the joint feels stiff and sore.

A Healthy Joint. In a healthy joint, the bones are encased in smooth cartilage. Together, they are protected by a joint capsule lined with a synovial membrane that produces synovial fluid. The capsule and fluid protect the cartilage, muscles and connective tissues.


place. You may hear a snapping sound as the tendon returns to its original position. In addition, your ligaments may tighten as you move your joints. This commonly occurs in your knee or ankle, and can make a cracking sound.

Rough surfaces: Arthritic joints make sounds caused by the loss of smooth cartilage and the roughness of the joint surface.

Is joint cracking harmful? If you are feeling pain when your joints pop, than you should seek a health care professional. In terms of knuckle cracking, some studies show that knuckle cracking does not cause serious harm. Other studies show that repetitive knuckle cracking can do some damage to the soft tissue of the joint. It may also lead to a weak grip and a swelling hand.

Q Can you tell the temperature by listening to the chirping of a cricket?

Yes! The frequency of chirping varies according to temperature. To get a rough estimate of the temperature in degrees fahrenheit, count the number of chirps in 15 seconds and then add 37. The number you get will be an approximation of the outside temperature.

So, how do crickets make that chirping sound?

Usually, the males are the “singers.” The male cricket rubs a scraper (a sharp ridge on his wing) against a series of wrinkles, or “files”, on the other wing. The tone of the chirping depends upon the distance between the wrinkles.

There are several reasons why crickets chirp. They may be:

a cricket


Calling to attract a female with a loud and monotonous sound Courting a nearby female with a quick, softer chirp Behaving aggressively during the encounter of two males Sounding a danger alert when sensing trouble

Q A bird lands on an uninsulated 10,000 volt power line. Will it become extra crispy?

No. Birds do this all the time. What protects the bird is the fact that it doesn‛t complete a circuit. It touches only one wire and nothing else. Although there is a substantial charge on the power line and some of that charge flows onto the bird when it lands, the charge movement is self-limiting. Once the bird has enough charge on it to have the same voltage as the power line, charge stops flowing. And even though the power line‛s voltage rises and falls 50 times a second the overall charge movement at 10,000 volts just isn‛t enough to bother the bird much. At 100,000 volts or more, the charge movement is uncomfortable enough to keep birds away, so you don‛t see them landing on the extremely high-voltage transmission lines that travel across vast stretches of countryside.

The story wouldn‛t be the same if the bird made the mistake of spanning the gap from one wire to another. In that case, current could flow through the bird from one wire to the other and the bird would run the serious risk of becoming a flashbulb. Squirrels occasionally do this trick when they accidentally bridge a pair of wires. Some of the unexpected power flickers that occur in places where the power lines run overhead are caused by squirrels and occasionally birds vaporizing when they let current flow between power lines.


Ais

for axon.

The Nervous System from A to Z

B is

for brain.

C is

for cortex.

Dis

for dendrite.

E is for EEG. Gis

for glia.

H is for hemisphere.

I is

for ion.

J is for jet lag. K is for knee jerk

reflex.

L is for limbic system.

M is for meninges.

Nis

for neuron.

O is for occipital lobe.

P is for parietal lobe.

Q is for quadriplegia.

R is for receptor.

S is for synapse.

T is for temporal lobe.

F is for frontal lobe.


Axon part of a neuron that takes information away from the cell body. Brain organ composed of billions of neurons and glial cells that coordinate all behavior. Cortex outermost layer of the cerebral hemisphere. Dendrite – part of a neuron that takes information to the cell body. EEG – the electroencephalogram; a record of electrical activity of the brain obtained from scalp electrodes. Frontal lobe area of the cerebral cortex involved with reasoning, planning, speech, movement and emotions. Glia support cells of the nervous system. Hemisphere one half of the brain Ion charged molecule. Jet lag symptoms that occur after traveling through many time zones. Knee jerk reflex kicking response seen after a tap just below the knee. Limbic system interconnected areas of the brain important for emotions. Meninges series of three membranes (dura mater, arachnoid, pia mater) that cover the brain and spinal cord.

Neuron a nerve cell. Occipital lobe area of the cerebral cortex important for vision. Parietal lobe area of the cerebral cortex involved with the perception of touch, pressure, temperature, and pain. Quadraplegia paralysis of all four limbs. Receptor membrane protein that can bind neurotransmitters; used in chemical communication between neurons. Synapse functional connection between one neuron and another neuron. Temporal lobe area of the cerebral cortex involved with memory and the perception and recognition of sounds. Unipolar a neuron with a single branch extending from the cell body. Vision the sense of sight. White matter nerve fiber pathways. Xrays short wave length radiation used to image the body. Yawn involuntary inspiration of air with the mouth wide open. Zinc a chemical element found in trace concentrations within the brain.

WORD GLOSSARY

U is for unipolar.

V is for vision. W is for white matter.

X is for x-ray.

Y is for yawn.

Z is for zinc.


Amaze your friends by making water defying gravity. It‛s a simple experiment that dramatically demonstrates the amazing physical properties of water.

What You Need : Tall glass with a round edge

A handkerchief

A pitcher of water

What You Do : 1. Drape the handkerchief over the glass making sure that you

push the center of the handkerchief down into the glass.

2. Fill the glass 3/4 full with water by pouring water into the middle of the handkerchief.

3. Slowly pull the handkerchief down the sides of the glass making it taut (stretched tightly across the surface of the glass). Grip the ends of the handkerchief at the bottom of the glass.

4. Place one hand over the mouth of the glass and turn it over with the other hand.

5. Pull the lower hand away from the glass (slowly) and the water

Anti‐Gravity Water


should stay in the glass! This just goes to prove that the handkerchief has anti-gravity properties.

6. For the big finish, put your hand over the mouth of the glass and turn the glass right side up. Remove the handkerchief from the glass and pour the water back into the pitcher.

How does it work? Most people predict that the water will leak through the holes in the handkerchief because the water leaked through the holes as it was poured into the glass. The holes in the handkerchief literally disappeared when the cloth was stretched tightly across the mouth of the glass. This action allowed the water molecules to bond to other water molecules creating what is called surface tension. The water stays in the glass even though there are tiny holes in the handkerchief because the molecules of water are joined together to form a thin membrane between each opening in the cloth. Be careful not to tip the glass too much because you‛ll break the surface tension and surprise everyone with a gush of water!

Great Physicists There are no physicists in the hottest parts of hell, because the existence of a “hottest part” implies a temperature difference, and any marginally competent physicist would immediately use this to run a heat engine and make some other part of hell comfortably cool. This is obviously impossible.


Nationwide Interactive Science Olympiad Sample Paper

1. The safest way to dilute concentrated sulphuric acid is to add (a) a series of small volumes of water to the acid while stirring (b) the acid to water slowly while stirring constantly (c) the acid to a small volume of water and then add more

water (d) dilute sulphuric acid to a small volume of the concentrated

acid. 2. The smell of an ammonia solution used to clean a floor can

quickly be detected throughout a house. Scientists explain this phenomenon by theorizing that gas molecules from the ammonia are in continuous random high-speed motion, drifting rapidly and permeating the air. Which statement best demonstrates the strength of this theory? (a) Scientists have observed tiny smoke particles moved by

unseen particles in a rapid, irregular fashion. (b) Scientists have unanimously agreed on this theory since

Thomas Graham‛s experiments in the 1820s. (c) The possibility of another theory being formed to explain

the phenomenon as well is very remote. (d) Reason, as opposed to experimentation, is superior to any

explanation found through chemical testing. 3. Four lab groups measured the volume of acid required to

neutralize a standard solution of sodium hydroxide base. Which of the groups measured the volume with the highest precision?

(a) (b)

10 - EduSys · · 2011-08-22Experiment Water Transport in Plant Stems 16 6. Invent Potato Clock...

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