Topik 4 - Periodic Table

7/28/2019 Topik 4 - Periodic Table

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PERIODIC TABLE

History of the development of the Periodic Table

1. Antoine Lavoisier

a. 1st person to classify elements

b. Group them into 4 groups

3. John Newlands

a. 1st to arrange elements in the

order of increasing atomic mass.

b. Law of Octate, later became Periodic Law.

c. Important to further the developmentof Periodic Table Johann Johann.

2. Johann W. dobereiner

Triad system

elements grouped in 3

4. Lothar Meyer

Graph of atomic volume

against atomic mass show

similar curve with similar

chemical properties.


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4. Dimitri Mendeleev

a. Arrange elements in the order of

increasing mass.

b. Left empty spaces for elements to be

found later.

A modern Periodic table

1. In the Periodic table, elements are arranged in the order of increasing proton

number.

2. Periodic table has 7 rows (Period) and 18 columns (Groups).

3. 1st, 2nd and 3rd are the short periods.

4. Period 4 and 5 are long periods, which included the transition metals.

5. Period 6 is lanthanide series.

6. Period 7 is actinide series.

6. H. J. G. Moseley

a. X-ray frequencies helped to

determine proton numbers.

b. Arranged elements in the order of

increasing proton number.


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GROUP 1 ELEMENTS

Alkali metal

Physical properties

Soft silvery solid, easily cut.

They are malleable and ductile.

They oxidize rapidly in air. Due to oxide coating, its bright, shiny luster is hidden. When the

coating is cut off with a knife, the shiny metal will be clearly visible.

These are good conductors of heat and electricity.

Good electricity conductor free moving valence electrons.

They are highly reactive with water. They are mostly not found in free nature as they react

quickly and vigorously. Some of these metals are stored in kerosene or other mineral oils.

Potassium and sodium metal store in paraffin oil


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Luminant, colorful flame is produced by them when burned with oxygen.

When going down the group,

Li, Na, K, Rb, Cs, Fr

Atomic size increasing

Softer

Density increasing number of protons and neutrons increase

bp, mp decreasing sizes,

Softness of the element down the group increases due to increasing atomic number becausethe metallic bond will decrease with increase in atomic size.

Chemical properties

1. Actively react with oxygen

2. Actively react with chlorine


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3. Reaction with water


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4.

Fun reading

LithiumLithium is the lightest metal discovered yet. It is the only metal that reacts with nitrogen.

Lithium Oxide is Amphoteric (both acid and base characteristics). Except Lithium, other

alkali elements are predominantly ionic. The charge density on Lithium is stronger than other

alkali metals due to which it is extensively hydrated. Lithium was discovered in 1817 by

Johan Arfvedson, during petalite LiAlSi4O10 analysis. The word Lithium is derived from the

Greek word 'lithos' meaning stone. Lithium is found in number of pegmatitic minerals, clays,

brines, oceans, and in all living things.

Uses of Lithium

Lithium is used in heat resistive ceramics and glasses.

Alloy of Lithium is used in aircraft building.

Lithium Deuteride is used as fusion fuel in thermonuclear weapons.

Lithium batteries are packed with lot of energy as compared to other metals. Revolutionized

devices like cell phones, computers use lithium batteries.

Lithium salts are used as mood stabilizing drug.

Lithium-6 is a main source for tritium production.

Lithium is used in deoxidizing copper and copper alloys.

Lithium compounds are used as pyrotechnic colorants in fireworks that produces red

luminance.


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Lubricating greases are produced from Lithium.

Sodium

Sodium is a chemical substance which we consume everyday in our food in the form of

sodium chloride (common salt). Sodium is produced by electrolysis of sodium chloride.

Sodium element is highly reactive. In 1806, Sir Humphry Davy, a chemist, obtained sodium

by passing electric current through molten sodium hydroxide. Sodium was first produced

through nuclear fusion in stars, by fusion of two carbon atoms. It can also be produced in

stars when neon atoms gain a proton.

Uses of Sodium

Sodium is used as luster in metals.

Liquid Sodium is used as coolant in Nuclear reactors.

Sodium salt of fatty acids are used in soap.NaK, an alloy of sodium and potassium, is an important heat transfer agent.

Sodium compounds are used in paper, textile, petroleum and chemical industries.

Sodium Iodide is used to treat extensive ringworm.

Sodium is used in street lights and sodium vapor lamps as it can give yellow glow with bright

luminance.

Sodium hydroxide is used as oven cleaner.

Potassium

Potassium is the 19th element in the periodic table. Potassium plays a vital role in the properfunctioning of our body. It is an essential mineral that should be maintained in organisms. If

potassium level is not balanced it may lead to hyperkalemia or hypokalemia. Potassium turns

gray on exposure to air. To prevent oxidation and to keep out moisture, potassium is stored in

petroleum.

Uses of Potassium

Potassium chloride is essential for the growth of plants. It is used in fertilizers.

Potash improves water retention, yield, nutrient value, taste, color, texture and disease

resistance of food crops.Potassium chlorate and potassium nitrate are used in explosives and fireworks.

Potassium nitrate is used as a food preservative.

Potassium maintains blood pressure and acidity levels in our body.

Potassium chromate is used in the tanning of leather and in the manufacture of inks, gun

powder, dyes, safety matches etc.,

Potassium is essential for normal cell respiration and electrolyte function as 95% of our cells

are made of potassium.

Potassium hydroxide is used to make detergents.

Potassium helps to pump fluids inside the heart and the nerves.


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Rubidium

Rubidium is a radioactive element. It is derived from a latin word rubius meaning deepest

red.

Uses of Rubidium

Rubidium 82 is used in myocardial perfusion.

Rubidium is used in the manufacture of atomic clocks, electronic tubes, photocells.

Rubidium is used as working fluid in vapor turbines.

It is used as a component in the engines of space vehicles.

Rubidium vapor is used in laser cooling.

Rubidium chloride is used to induce cells to take up DNA.

It is used in thermoelectric generators.

Rubidium Carbonate is used in making optical glasses.

Due to hyperfine structure of rubidium's energy levels, it is used in atomic clocks.

A compound made up of rubidium, silver and iodine, has certain electrical characteristics and

is used in making thin film batteries.

Cesium

Cesium is an active metal. Chemically, cesium is the most electropositive element and

combines with anions to form compounds. It is a highly toxic element. Cesium hydroxide isthe strongest base discovered yet. It has many isotopes of which cesium-133 is a stable

isotope and the most important standard for measurement of time (Cesium clocks or atomic

clocks). Cesium is liquid at or near room temperature.

Uses of Cesium

Cesium-134 is used in nuclear power industry.

Used in photoelectric cells due to its quick electron emission.

Cesium is used as catalyst for hydrogenation of certain organic compounds.

It is used in propulsion systems.It removes air traces from vacuum tubes.

Cesium is used in photovoltaic cells, television image devices, night-vision equipment.

Cesium vapor is used in magnetometer.

Cesium-137 is used in brachytherapy to treat cancers. (Brachytherapy is a cancer treatment

method using radioactive elements)

Cesium chloride solution is used in molecular biology for density gradient

ultracentrifugation, primarily for the isolation of viral particles, subcellular organelles and

fractions, and nucleic acids from biological samples.

Cesium is used as a standard in spectrophotometry

It is used in military aircraft.


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Francium

Francium has the lowest electronegativity among all the known elements. It is a highly

radioactive metal and heaviest of these metals. Francium is produced by bombarding thorium

with protons or by bombarding radium with neutrons. This element is rare and is not used

much. It is mainly used for scientific research in laboratory. It decays quickly as it has short

half life.

GROUP 17 ELEM,ENTS

Halogen : Fluorine(F), chlorine(Cl), bromine(Br), iodine(I)


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F2 Cl2 Br2 I2

Gas Gas Liquid Solid

Pale yellow Pale green Brown Black

--------------- size increase ---------------

--------------- reactivity decrease ----------

--------- m/p , b/p increase ( van der waal increase)--

---------- solubility decrease ----------

GROUP 18 ELEMENTS : Noble gas

He, Ne, Ar, Kr, Xe, Rn

Stable electronic structures, He duplet, others octet

Least reactive of all.

Low melting point and boiling point but increase gradually (Van der waals forces increase

with size/mass)

Size increase (no of shell increase)

Mass and density increase.

Uses of noble gases


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The Electron Configurations for Noble Gases: Group 18

Helium 2Neon 2.8Argon 2.8.8Krypton 2.8.18.8Xenon 2.8.18.18.8Radon 2.8.18.32.18.8

Trends within Group 18

Atomic

#

Atomic

mass

Boiling

point

(K)

Melting

point

(K)

Density

(g/dm3)

Atomic

radius/pm

He 2 4.003 4.216 0.95 0.1786 31

Ne 10 20.18 27.1 24.7 0.9002 38

Ar 18 39.948 87.29 83.6 1.7818 71

Kr 36 83.3 120.85 115.8 3.708 88Xe 54 131.29 166.1 161.7 5.851 108

Rn 86 222.1 211.5 202.2 9.97 120

The Atomic and Physical Properties Atomic mass, boiling point and atomic radii INCREASE down a group in the

periodic table.

The first ionization energy, DECREASES down a group in the periodic table.

The noble gases have the largest ionization energies which reflects their chemical

inertness.


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As you go down group 18, atomic radius and inter-atomic

forces INCREASES resulting in anINCREASED melting point, boiling point,

enthalpy of vaporization and solubility.

Group 18's INCREASE in density is correlated to the INCREASE in atomic mass.

Because they are INCREASING in atomic size, the electron clouds of these non

polar atoms become increasingly polarized which leads to weak van Der Waals forces

among the atoms. Thus, the formation of liquids and solids is more easily attainable

for these heavier elements because of their melting and boiling points.

Because noble gases outer shell is full, they are extremely stable, not tending to form

chemical bonds and have a low tendency to gain or lose electrons.

Under standard conditions the members of the noble gas group behave similarly.

All are monotomic gases under standard conditions.

Noble gas atoms, like other atoms in other groups, INCREASE steadily in atomic

radius from one period to the next due to the INCREASING number of electrons.

The size of the atom is positively correlated to several properties of noble gases. The

ionization potential DECREASES with an INCREASING radius, because the

valence electrons in the larger noble gases are further away from the nucleus, so they

are not being held as tightly together by the atom.

The attractive force INCREASES with the size of the atom as a result of

an INCREASE in polarizability and thus a DECREASE in ionization potential.

Overall, noble gases have weak interatomic forces, and therefore very low boiling andmelting points compared to other group elements.


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Helium

Helium can be found in

balloons!

Neon

One of the many

colors of neon lights.

Neon

Argon plasma light bulb.

Kripton

Krypton laser.

Xenon

Xenon headlights found in

BMW cars.

Radon

Radon bath


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PATTERN OF PROPERTIES IN A PERIOD

Na Mg Al Si P S Cl Ne

Solid Solid Solid Solid Solid Solid Gas Gas

Metal Metal Metal Metalloid Non

metal

Non

metal

Non

metal

Non

metal

Melting and boiling point

Electricity conductivity

TRANSITION METALSc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn


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The History Behind Noble Gases

The first person who set apart and characterized the presence of thesenoble gases was Henry Cavendish in 1875. Cavendish was able todistinguish these elements by chemically removing all the oxygen andnitrogen from a receptacle containing air. The nitrogen was oxidized toNO2 by electric discharges and absorbed by a sodium hydroxidesolution. The remaining oxygen was then removed from the mixture.Interestingly, the experiment revealed that 1/120 of the gas volumeremained un-reacted in the receptacle. The second person who wasable to isolate, but not typify them was William Francis (1855-1925).Francis did this by noting the formation of gas while dissolvingUranium containing minerals in acid.

Argon

In 1894, John William Strutt discovered that pure nitrogen, chemicallyobtained, was less dense compared to "pure" nitrogen isolated fromair. From this breakthrough, he concluded that something else was inthe air. With the aid and collaboration with William Ramsay, the twowere able to replicate and modify Cavendish's experiment to get abetter understanding of the un-reactive fraction of air in his original

experiment. Different from Cavendish, Strutt and Ramsay removed theoxygen by reacting it with copper and nitrogen was removed byreacting it with magnesium. The remaining fraction was properlycharacterized and the new element was named 'Argon' which camefrom the Greek word 'inert'.

Helium

Helium was first discovered as a bright yellow line with a wavelength of

587.49 nanometers from the sun in 1868. This discovery was made byPierre Jansen. Jansen initially assumed that it was sodium. However,later studies by Sir William Ramsay (who isolated helium on Earth bytreating a variety of rare elements with acids) confirmed that thebright yellow line that came out of the experiment matched up with thespectrum of the sun. From this, British physicist William Crookes wasable to identify it as helium.

Neon, Krypton, Xenon


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These noble gases discovered by Morris W. Travers and Sir WilliamRamsay in 1898. Ramsay discovered Neon by chilling a sample of theatmosphere until liquid phase, then captured the gases as the boiledoff by warming up the liquid. Krypton and Xenon were both discoveredthrough this process.

Radon

In 1900, while studying radium's decay chain, Friedrich Earns Dorndiscovered the last noble gas in group 18; Radon. Through someexperiments, Dorn noticed that radium compounds emanatedradioactive gas. This radioactive gas was originally named niton afterthe Latin word "nitens". By 1923, the International Committee forChemical Elements and International Union of Pure Applied Chemistry

(IUPAC) decided to name the element as Radon. All isotopes of radonare radioactive. Radon-222 has the longest half-life - less than 4 days,and is an alpha-decay product of Radium-226, part of the U-238 to Pb-206 radioactive decay chain.

For covalently-bonded diatomic and polyatomic gases, heat capacityconsists of translational, rotational, and vibrational fractions. Sincemonatomic gases such as noble gases have no bonds, they cannotabsorb heat as bond vibrations. Since the center of mass of

monatomic gases is at the nucleus of the atom, and the mass of theelectrons is negligible compared to the nucleus, the kinetic energy dueto rotation is negligible compared to the kinetic energy of translation,unlike in di- or polyatomic molecules where rotation of nuclei aroundthe center of mass of the molecule contributes to the heat capacity.Therefore, the internal energy per mole of a monatomic noble gasequals its translational contribution = (3/2) R T, where R = universalgas constant and T = absolute temperature.

For monatomic gases at a given temperature, the average kinetic

energy due to translations of the atoms is practically equal regardlessof the element. Therefore at a given temperature, the heavier theatom, the more slowly its gas atoms will move. Monatomic gas meanvelocity DECREASES with increasing molecular mass, and given thesimplified heat capacity situation, noble gaseous thermal conductivityDECREASES with increasing molecular mass.

The Uses of Noble Gases in Everyday Life


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Helium

is used as a component of breathing gases due to its low solubility influids or lipids. For example, gases are absorbed by the blood and

body tissues when under pressure during scuba diving. Because of itsreduced solubility, little helium is taken into cell membranes, when itreplaces part of the breathing mixture, helium causes a decrease in thenarcotic effect of the gas at far depths. The reduced amount ofdissolved gas in the body means fewer gas bubbles form decreasingthe pressure of the ascent. Helium and Argon are used to shieldwelding arcs and the surrounding base metal from the atmosphereduring welding.

Helium can be found in balloons!

Helium is used in very low temperature cryogenics, particularly formaintaining superconductors at a very low temperature.Superconductivity is useful for creating very strong magnetic fields.Helium is also the most common carrier gas in gas chromatography.

Neon

is used for many applications that we see in daily life. For examples:

Neon lights, fog lights, TV cine-scopes, lasers, voltagedetectors, luminous warnings and also advertising signs. The mostpopular applications of Neon would be the Neon tubes that we see foradvertisement or elaborate decorations. These neon tubes consist withneon and helium or argon under low pressure submitted to electricaldischarges. The color of emitted light shown is dependent on thecomposition of the gaseous mixture and also with the color of the glassof the tube. Pure Neon within a colorless tube can obtain a red light,which reflects a blue shine. These reflected light are also known asfluorescent light.

Argon

Argon is used for a diverse group of applications in the growingindustries of : electronics, lighting, glass, and metal fabrications. Argonis used in electronics to provide a protective heat transfer medium forultra-pure semiconductors from silicon crystals and for growinggermanium. Argon can also fill fluorescent and incandescent lightbulbs; creating the blue light found in neon type lamps. By utilizingargon's low thermal conductivity, window manufacturers can provide agas barrier needed to produce double-pane insulated windows. This
http://chemwiki.ucdavis.edu/Analytical_Chemistry/Instrumental_Analysis/Chromatography/Gas_Chromatographyhttp://chemwiki.ucdavis.edu/Analytical_Chemistry/Instrumental_Analysis/Chromatography/Gas_Chromatography


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Radon

Radon has been said to be the second most frequent cause of lungcancer, after cigarette smoking. However, it can be found in various

beneficial applications as well. For examples through: radiotherapy,relief from arthritis, and bathing. In radiotherapy, radon has been usedin implantable seeds, made of glass or gold, primarily used to treatcancers. For arthritis, its been said that exposure to radon mitigatesauto-immune diseases such as arthritis. Those who have arthritis haveactually sought limited exposure to radioactive mine water and radonto relief their pain. However, radon has nevertheless found to inducebeneficial long-terms effect. Some places actually have "Radon Spas".For examples: Bad Gastern, Austria and Japanese Onsen in Misasa,Tottori. "Radon Spa" is a relieving therapy where people sit for minutes

to hours in a high-radon atmosphere, believing that low doses ofradiation will boost up their energy.

Radon bath.Uses of Alkali Metals

In IUPAC (International Union of Pure and Applied Chemistry)

nomenclature, alkali metals or Group 1A elements belong to group 1A in

the periodic table. Scroll down to learn about the uses of alkali metals.

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Alkali metals or Group 1A elements belong to a common group due to its

ns1 valence electronic configuration. The properties of an element have

periodic dependence on its atomic number but not on atomic weight.

These are similar to Group 17 (Halogens) in a way that, it attains noble

gas configuration after losing its valence electron. That is why hydrogen is

placed separately in the periodic table. Alkali elements belong to s-block,

including hydrogen.

Properties

These metals are soft, shiny, silvery white elements.

They are highly reactive with water. They are mostly not found in free

nature as they react quickly and vigorously. Some of these metals are

stored in kerosene or other mineral oils.

They oxidize rapidly in air. Due to oxide coating, its bright, shiny luster is

hidden. When the coating is cut off with a knife, the shiny metal will be

clearly visible.Luminant, colorful flame is produced by them when burned with oxygen.


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These have low ionization enthalpy (heat evolved when an atom gets

ionized).

These are strong reducing agents.

They are malleable and ductile.

Softness of the element down the group increases due to increasingatomic number because the metallic bond will decrease with increase in

atomic size.

The ionization energy of group 1A elements decreases down the group.

These are good conductors of heat and electricity.

Element Symbol Atomic

number Electronic

configuration Melting

point Boilingpoint

Lithium Li 3 1s22s1 180.54C 1342C

Sodium Na 11 3s1 97.72C 883C

Potassium K 19 4s1 63.38C 759C

Rubidium Rb 37 5s1 39.31C 688C

Cesium Cs 55 6s1 28.44C 671C

Francium Fr 87 7s1 27C 677C

Lithium

Lithium is the lightest metal discovered yet. It is the only metal that reacts with nitrogen.

Lithium Oxide is Amphoteric (both acid and base characteristics). Except Lithium, other

alkali elements are predominantly ionic. The charge density on Lithium is stronger than other

alkali metals due to which it is extensively hydrated. Lithium was discovered in 1817 by

Johan Arfvedson, during petalite LiAlSi4O10 analysis. The word Lithium is derived from the

Greek word 'lithos' meaning stone. Lithium is found in number of pegmatitic minerals, clays,

brines, oceans, and in all living things.

Uses of Lithium

Lithium is used in heat resistive ceramics and glasses.

Alloy of Lithium is used in aircraft building.

Lithium Deuteride is used as fusion fuel in thermonuclear weapons.

Lithium batteries are packed with lot of energy as compared to other metals. Revolutionized

devices like cell phones, computers use lithium batteries.

Lithium salts are used as mood stabilizing drug.

Lithium-6 is a main source for tritium production.

Lithium is used in deoxidizing copper and copper alloys.

Lithium compounds are used as pyrotechnic colorants in fireworks that produces red


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luminance.

Lubricating greases are produced from Lithium.

Sodium

Sodium is a chemical substance which we consume everyday in our food in the form ofsodium chloride (common salt). Sodium is produced by electrolysis of sodium chloride.

Sodium element is highly reactive. In 1806, Sir Humphry Davy, a chemist, obtained sodium

by passing electric current through molten sodium hydroxide. Sodium was first produced

through nuclear fusion in stars, by fusion of two carbon atoms. It can also be produced in

stars when neon atoms gain a proton.

Uses of Sodium

Sodium is used as luster in metals.

Liquid Sodium is used as coolant in Nuclear reactors.

Sodium salt of fatty acids are used in soap.

NaK, an alloy of sodium and potassium, is an important heat transfer agent.

Sodium compounds are used in paper, textile, petroleum and chemical industries.

Sodium Iodide is used to treat extensive ringworm.

Sodium is used in street lights and sodium vapor lamps as it can give yellow glow with bright

luminance.

Sodium hydroxide is used as oven cleaner.

Potassium

Potassium is the 19th element in the periodic table. Potassium plays a vital role in the properfunctioning of our body. It is an essential mineral that should be maintained in organisms. If

potassium level is not balanced it may lead to hyperkalemia or hypokalemia. Potassium turns

gray on exposure to air. To prevent oxidation and to keep out moisture, potassium is stored in

petroleum.

Uses of Potassium

Potassium chloride is essential for the growth of plants. It is used in fertilizers.

Potash improves water retention, yield, nutrient value, taste, color, texture and disease

resistance of food crops.

Potassium chlorate and potassium nitrate are used in explosives and fireworks.

Potassium nitrate is used as a food preservative.

Potassium maintains blood pressure and acidity levels in our body.

Potassium chromate is used in the tanning of leather and in the manufacture of inks, gun

powder, dyes, safety matches etc.,

Potassium is essential for normal cell respiration and electrolyte function as 95% of our cells

are made of potassium.

Potassium hydroxide is used to make detergents.

Potassium helps to pump fluids inside the heart and the nerves.

Rubidium


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Rubidium is a radioactive element. It is derived from a latin word rubius meaning deepest

red.

Uses of Rubidium

Rubidium 82 is used in myocardial perfusion.Rubidium is used in the manufacture of atomic clocks, electronic tubes, photocells.

Rubidium is used as working fluid in vapor turbines.

It is used as a component in the engines of space vehicles.

Rubidium vapor is used in laser cooling.

Rubidium chloride is used to induce cells to take up DNA.

It is used in thermoelectric generators.

Rubidium Carbonate is used in making optical glasses.

Due to hyperfine structure of rubidium's energy levels, it is used in atomic clocks.

A compound made up of rubidium, silver and iodine, has certain electrical characteristics and

is used in making thin film batteries.

Cesium

Cesium is an active metal. Chemically, cesium is the most electropositive element and

combines with anions to form compounds. It is a highly toxic element. Cesium hydroxide is

the strongest base discovered yet. It has many isotopes of which cesium-133 is a stable

isotope and the most important standard for measurement of time (Cesium clocks or atomic

clocks). Cesium is liquid at or near room temperature.

Uses of CesiumCesium-134 is used in nuclear power industry.

Used in photoelectric cells due to its quick electron emission.

Cesium is used as catalyst for hydrogenation of certain organic compounds.

It is used in propulsion systems.

It removes air traces from vacuum tubes.

Cesium is used in photovoltaic cells, television image devices, night-vision equipment.

Cesium vapor is used in magnetometer.

Cesium-137 is used in brachytherapy to treat cancers. (Brachytherapy is a cancer treatment

method using radioactive elements)

Cesium chloride solution is used in molecular biology for density gradient

ultracentrifugation, primarily for the isolation of viral particles, subcellular organelles and

fractions, and nucleic acids from biological samples.

Cesium is used as a standard in spectrophotometry

It is used in military aircraft.

Francium

Francium has the lowest electronegativity among all the known elements. It is a highly

radioactive metal and heaviest of these metals. Francium is produced by bombarding thorium

with protons or by bombarding radium with neutrons. This element is rare and is not usedmuch. It is mainly used for scientific research in laboratory. It decays quickly as it has short


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half life.

Topik 4 - Periodic Table

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