MASTERING ESSAY QUESTION IN PAPER 3

Experiment 1 (Chapter 2) Experiment 2 (Chapter 4) SPM 2008 Experiment 3 (Chapter 4) Aim: To investigate the effect of the presence of impurity to the melting point of naphthalene (becomes lower)

Aim:To investigate the reaction of alkali metals in water

Aim:To investigate the reactions of alkali metals with oxygen / chlorine

Problem statement:How does

Problem statement:How does reactivity of Group 1 elements change when they react with water?

Problem statement:How do alkali metal react with oxygen / chlorine?

Variables: Manipulated: Responding:Fixed (controlled):

Variables: Manipulated: types of alkali metalResponding: reactivity of alkali metal Fixed (controlled): size of alkali metal

Variables: Manipulated: types of alkali metalsResponding: reactivity of alkali metalsFixed (controlled): oxygen gas

Hypothesis: Hypothesis: When going down Group 1, alkali metal becomes more reactive in water.

Hypothesis: When going down Group 1, alkali metals becomes more recative in their reaction with oxygen

Materials: Materials: red litmus paper, distilled water, paper, filter paper, small lithium,sodium and potassium

Materials: 3 gas jar filled with oxygen, red litmus paper, paper, filter paper, small lithium,sodium and potassium

Apparatus: Apparatus: water through, knife, forceps Apparatus: gas jar spoon, gas jar cover, small knife, Bunsen burner, pair of forceps

Procedure: Procedure:1) A piece of lithium removed from the bottle with apair

of forceps.2) A small piece of lithium is cut using a knife.3) The paraffin oil on the surface of lithium is removed

by using a piece of filter paper.4) The piece of lithium is placed into a water through

half-filled with cold distilled water using pair of forceps.

5) When the reaction stops, a piece of red litmus paper is put into the solution formed.

6) All changes occured are recorded.7) Steps 1 to 6 is repeated using potassium and sodium

respectively to remove lithium.

Procedure:1) A piece of lithium removed from the bottle with a

pair of forceps.2) A small piece of lithium is cut using a knife.3) The paraffin oil on the surface of lithium is removed

by using a piece of filter paper.4) The piece of lithium is placed in a gas jar spoon.5) The lithium is start to burn when heated.6) The burning lithium quickly lowered into a gas jar

filled with oxygen.7) When recations stops, 20cm3 of distilled water is

poured into gas jar and shaken well.8) A piece of red litmus paper is put into solution

formed.9) All changes that occured are recorded.10) Steps 1 to 9 is repeated using potassium and sodium

respectively to remove lithium.Tabulation of data: Tabulation of data:

Metal ObservationLithiumSodiumPotassium

Tabulation of data:Metal Observation

LithiumSodiumPotassium

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Experiment 4 (Chapter 4) Experiment 5 (Chapter 6) Experiment 6 (Chapter 6)Aim: To investigate the reaction of halogens with iron

Aim: To investigate the effect of concentration of ions on the selective discharge of ions at the electrodes of aqueous hydrochloric acid

Aim:To investigate the effect of the type of electrodes on the products of electrolysis of aqueous copper(II) sulphate solution.

Problem statement: How does reactivity of halogens change when they react with iron

Problem statement: How does the concentration of ions in hydrochloric acid affect the discharge of ions at the anode?

Problem statement:How does the type of electrodes affect the type of products formed during the electrolysis

Variables: Manipulated: types of halogensResponding: reactivity of halogensFixed (controlled): iron

Variables: Manipulated: concentration of chloride ionsResponding: ion discharged at the anodeFixed (controlled): type of electrode

Variables: Manipulated: types of electrodesResponding: types of product at anodeFixed (controlled): type of electrolyte

Hypothesis: The reactivity of halogens decreases down the group from chlorine to bromine when they react with iron.

Hypothesis: When the concentration of chloride ion is higher, then the chloride ion will be preferentially discharged.

Hypothesis: When copper electrodes are used instead of carbon electrodes, the types of products formed at the anode are different

Materials: potassium manganate (VII) crystal, concentrated HCL, liquid bromine, iodine crystals, soda lime and iron wool

Materials: 1.0 moldm-3 hydrochloric acid, 0.001 moldm-3 hydrochloric acid

Materials: 0.1 moldm-3 Copper (II) sulphate solution

Apparatus: test tubes, test tube holders, rubbber stoppers, conical flask, combustion tube, delivery tube, Bunsen burner, retort stand with clamp, thistle funnle.

Apparatus: batteries, carbon electrodes, connecting wires, ammeter, electrolytic cell, tet tube, blue litmus paper, wooden splinter and matches

Apparatus: batteries, carbon, copper electrodes, connecting wires, ammeter, electrolytic cells, sandpaper, wooden splinter and matches

Procedure:1) A little iron wool is placed in the middle of

combustion tube and heated strongly.2) Concentrated HCL/liquid bromine/iodine crystal

is heated gently in test tube.3) Chlorine gas/bromine gas/iodine vapour

liberated is passed through the heated iron wool in the combustion tube until no further changes occur.

4) The excess chlorine gas/bromine gas/iodine vapour is absorbed by soda lime.

5) All changes are observed and recorded.

Procedure:1) An electrolytic cell filled with 1.0 moldm-3

hydrochloric acid until it is half full.2) The circuit is completed by connecting the electrodes

to the switch, ammeter, and batteries.3) The switch is turned on.4) Any observation is recorded.5) The gas produced at anode and cathode are

collectedand tested with a moist blue litmus paper and a lighted wooden splinter,

6) Step 1 to 4 is repeated using 0.001 moldm-3 hydrochloric acid to replace 1.0 moldm-3 hydrochloric acid.

7) The gas produced at the anode and cathode are collected and tested with glowing wooden splinter and lighted wooden splinter.

Procedure:1) Two carbon electrodes are cleaned with

sandpaper.2) The Copper (II) sulphate solution is poured into

an electrolytic cell with carbon electrodes until it is half full.

3) The circuit is completed by connecting the electrodes to the switch, ammeter, and batteries.

4) The switch is turned on foor 15 min.5) All observation at the anode, cathode and

electrolyte are recorded.6) Gas produced at anode is collected and tested

with glowing wooden splinter.7) Step 1 to 5 is repeated using copper electrodes

Tabulation of data:Halogens Observation Chlorine Bromine Iodine

Tabulation of data:Electrolyte Observation

Anode Cathode 1.0 HCL

0.001 HCL

Tabulation of data:Electrode Observation

Anode Cathode ElectrolyteCarbonCopper

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Experiment 7 (Chapter 6) SPM 2007 Experiment 8 (Chapter 6) Experiment 9 (Chapter 7) Aim: To construct the electrochemical series based on potential differences between metals

Aim:To construct the electrochemical series using the principle of displacement of metals

Aim:To investigate the role of water in showing their properties of acids

Problem statement:Can an electrochemical series of metals be constructed based on the potential difference between two metals?

Problem statement:How can the electrochemical series of metals be constructed based on the displacement metals?

Problem statement:Is water neede for an acid to show its acidic properties?

Variables: Manipulated: pairs of metalsResponding: potential difference producedFixed (controlled): type and concentration of electrolye

Variables: Manipulated: metal strips/salt solution usedResponding: deposition of metalsFixed (controlled): concentration of salt solution

Variables: Manipulated: types of solventResponding: change in colour of blue litmus paperFixed (controlled): type of acid

Hypothesis: The further apart the two metals in the electrochemical series, the greater the potential difference produced/voltage produced.

Hypothesis: The greater the number of metals that can be displaced by a metal from their solutions, the higher is its position in the electrochemical series.

Hypothesis: an acid will show its acidic properties when dissolves in water.

Materials: 0.1 moldm-3 sulphuric acid, copper strip, lead, iron, zinc, aluminium, magnesium strip, sand paper

Materials: 1.0 mol dm-3 of magnesium nitrate, zinc nitrate, lead nitrate, copper nitrate, magnesium, zinc, lead and copper strips, sandpaper

Materials: glacial ethanoic acid, distilled water, dry propanone, blue litmus paper

Apparatus: 250 cm3 beaker, crocodile clips, voltmeter, and connecting wires.

Apparatus: test tubes, test tube rack Apparatus: test tube, droppers, tets tube rack

Procedure:1) The metal strips are celaned with sanpaper.2) A beaker filled with dilute sulphuric acid until two-

thirds full.3) Magnesium strip as electrode A and copper strip as

electrode B are dipped into dilute sulphuric acid.4) The circuit is completed by connecting the metals to

a voltmeter.5) The reading of voltmeter produced is recorded.6) The metal strip that acts as the negative terminal is

determined and recorded.7) Step 1 to 6 are repeated using aluminium, zinc, lead,

iron, and copper to replace magnesium as electrode A.

Procedure:1) The strips are clened with sandpaper.2) 5cm3 og magnesium nitrate, zinc nitrate, lead

nitrate, copper nitrate solution are poured into 4 separate tubes.

3) A strip of magnesium is placed into each of the solutions.

4) Observation on the deposition of metals are recorded.

5) Steps 1 to 4 are repeated using zinc, lead and copper to replace magnesium strip.

Procedure:1) Three test tubes are labelled as A, B, and C.

They are placed in test tube racks.2) 1cm3 of glacial ethanoic acid is placed into each

test tubes usind a dropper.3) 2cm3 of distilled water is added to test tube B.4) 2cm3 of dry propanone added to test tube C.5) A piece of dry blue litmus paper is placed into

each test tube.6) Any changes that occur are observed and

recorded.

Tabulation of data:Pair of metal + terminal -terminal Voltage

Zn/CuMg/CuAl/CuAg/CuFe/Cu

Tabulation of data:Metal strip Mg(NO3) Zn(NO3)2 Pb(NO3)2 Cu(NO3)2

MagnesiumZincLead

Copper

Tabulation of data:Test tube Observation

ABC

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Experiment 10 (Chapter 2) Experiment 11 (Chapter 7) SPM 2009 Experiment 12 (Chapter 8) Aim: To investigate the role of water in showing their properties of alkalis

Aim:To investigate the relationship between pH values with molarity of acid

Aim:To construct the ionic equation for the concentration for the formation of lead(II) chromate(VI)

Problem statement:Is water needed for an alkali to show its alkali properties?

Problem statement:What is the relation between pH values with molarity of an acid?

Problem statement:How to construct an ionic equation for the formation of lead(II) chromate(VI)?

Variables: Manipulated: types of solventsResponding: chnage in colour of red litmus paperFixed (controlled): type of alkali and litmus paper

Variables: Manipulated: molarity of acidResponding: pH valuesFixed (controlled): type of acid

Variables: Manipulated: volumes of lead(II) nitrate solutionResponding: height of yellow precipitateFixed (controlled): volumes of potassium chromate(VI) soution

Hypothesis: an alkali will only show its alkaline properties when dissolve in water

Hypothesis: When the molarity of acid increases, its pH values increases

Hypothesis: as the volume of potassium chromate(VI) solution increases, the height of the yellow precipitate increases untill all the lead (II) nitrate has reacted.

Materials: dry ammonia gas stoppered in atest tube, ammonia gas dissolved in propanone, aqueous ammonia solution and red litmus paper.

Materials: hydrocloric acids of 1.0 mol dm-3, 0.1 mol dm-3, 0.01 mol dm-3, 0.001 mol dm-3

Materials: 0.5 mol dm-3 lead (II) nitrate solution and o.5 mol dm-3 potassium chromate (VI) solution

Apparatus: test tubes and droppers Apparatus: pH meter, 100cm3 beakers, and 100cm measuring cylinder

Apparatus: test tubes of the same size, test tube rack, 50cm3 burette, retort stand with clamp and ruler

Procedure:1) A piece of dry litmus paper is put into a

stoppered test tube of dry ammonia gas and the test tube is then stoppered back immediately.

2) The effect of the dry ammonia gas on the red litmus paper is recorded.

3) Another piece of dry red litmus aper is put in 5cm3 of aqueous ammonia solution in aseparate test tube.

4) Step 3 of the experiment is repeated using ammonia dissolved in propanone to replace aqueous ammonia solution.

Procedure:1) 30cm3 of 1.0 mol dm-3 hydrochloric acid is put

in dry beaker.2) The probe of a pH meter that has been washed

with distilled water is immersed in 30 cm3 of the 1.0 mol dm-3 hydrochloric acid.

3) The pH values shown on the pH meter is recorded.

4) The pH values of hydric acid solutions with different molarities are measured one by one in dry beakers as in steps 1 to 3.

Procedure:1. 7 test tubes of same size are labelled from 1 to 7.

They are placed on test tube rack.2. A burette is filled with 0.5 moldm-3 potassium

chromate (VI) solution. 5.0 moldm-3 of the potassium chromate (VI) solution is placed into each test tube.

3. Another burette is filled with 0.5 moldm-3 lead (II) nitrate solution.

4. lead (II) nitrate solution from the burette is added into each of the 7 test tubes.

5. The mixture in each test tube is stirred using glass rod. A yellow precipitate is formed in each test tube.

6. The test tubes are left aside for about an hour.7. The height of precipitate in each test tube is

measured using metre rule. The colour above the precipitate in each test tube is observed and recorded.

Tabulation of data:Condition of

ammoniaObservation Inference

Tabulation of data:Molarities (mol dm-3) pH values

1.00.10.010.001

Tabulation of data:Test tube 1 2 3 4 5 6 7Volume of 0.5 moldm-3 potassium chromate (VI) solutionVolume of 0.5 moldm-3 lead (II) nitrate solution.Height of precipitateColour of solution above precipitate

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Experiment 13 (Chapter 9) SPM 2003/05 Experiment 14 (Chapter 9) SPM 2003 Experiment 15 (Chapter 10) Aim: To compare the hardness of pure metal and its alloy

Aim:To compare the rate of rusting between iron, steel and stainless steel

Aim:To investigate the effect of total surface area of the reactant on the rate of reaction

Problem statement:Are alloys harder than pure metal?( is bronze harder than copper )

Problem statement:How does the rate of rusting between iron, steel and stainless steel differ?

Problem statement: How does the total exposed surface area of a solid reactant affect the rate of reaction?

Variables: Manipulated: types of materials to make the metal blockResponding: diameter of the dent made by a steel ball bearingFixed (controlled): size of steel ball bearing

Variables: Manipulated: types of nails(iron, steel, stainless steel)Responding: rate of rustingFixed (controlled): size of nails

Variables: Manipulated: size of marble chipsResponding: rate of reactionFixed (controlled): temperature

Hypothesis: Bronze is harder than copper Hypothesis: pure iron rusts faster than steel while stainless steel does not rust easily

Hypothesis: When the total surface area of marble chips increases, the rate of reaction increases

Materials: copper block, bronze block, ball beraing, cellophane tape and thread

Materials: iron nail, steel nail, stainless steel nail, 5% jelly solution and potassium hexacyanoferrate(III) solution and sandpaper

Materials: 80cm3 0.1moldm-3 hydrochloric acid, 2g large marble chip, 2g small marble chip, water

Apparatus: metre rule, retort stand with clamp, 1 kg weight

Apparatus: test tubes

Apparatus: 50cm3 measuring cylinder, 150cm3 conical flask, stopper with delivery tube, basin, burette, electronic balance, stopwatch

Procedure:1) A metre rule is clamped to a retort stand, and a piece

of copper block is placed on the based of the retort stand.

2) A steel ball bearing is placed on the copper block and a piece of cellophane tape is used to hold the ball bearing in place.

3) A 1 kg weight is hung at a height of 50 cm above the copper block.

4) The weight is dropped onto the ball bearing placed on the copper block.

5) The diameter of the dent made by the ball bearing is measured to the nearest 0.5mm.

6) Step 1 to 5 is repeated using bronze block to replace copper block.

Procedure:1) Three test tubes are half filled with jelly solution

and are labelled as A, B and C.2) 1 cm3 of potassium hexacyanoferrate (III)

solution is added to every test tube.3) An iron nail, a steel nail and a stainless steel are

polished with sandpaper to remove any rust formed. The nails are then placed in the three test tubes labelled A, B and C respectively.

4) All test tubes are allowed to stand for 2 days before they are examiined.

5) Changes occurred on the nail are observed and recorded.

Procedure:1) Fill a burette with water and invert it over water in a

basin.2) Clamp the burette vertically using a retort stand.

Records its initial reading.3) Measure 40cm3 of 0.1 moldm-3 hydrochloric acid,

HCL using a measuring cylinder. Transfer the acid into a conical flask.

4) Weigh 2g of large marble chips. Put them into the conical flask. Close the conical flask immediately with astopper which is joined to the delivery tube and start the stopwatch.

5) Record the burette reading at intervals of 30 seconds until the reaction stops.

6) Repeate the steps 1 to 6 using 2g of small marble chips to replace 2g of large marble chips.

Tabulation of data:MetalBlock

Diameter of dent (mm)I II II average

CopperBronze

Tabulation of data:Test tube Type of nail Observation

A Iron nailB Steel nailC Stainless steel nail

Tabulation of data:Times

Burette reading

Volume gas

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Experiment 16 (Chapter 10) Experiment 17 (Chapter 10) Experiment 18 (Chapter 10) SPM 2010Aim: To investigate the effect of concentration on the rate of reaction

Aim:To investigate the effect of temperature on the rate of reaction

Aim:To investigate the effect of catalyst on the rate of recation

Problem statement:How does the concentration of reactant affect the rate of reaction?

Problem statement:How does the temperature affect the rate of reaction?

Problem statement:How does catalyst affect the rate of reaction?

Variables: Manipulated: concentration of sodium thiosulphate solution Responding: time taken for the cross ‘X’ to disappearFixed (controlled): concentration dilute sulphuric acid

Variables: Manipulated: temperature of sodium thiosulphate solutionResponding: time taken for the cross ‘X’ to diasappearFixed (controlled): concentration of sodium thiosulphate solution

Variables: Manipulated: amount of catalyst usedResponding: the volume of oxygen given off at half-minute intervalsFixed (controlled): volume of hydrogen peroxide

Hypothesis: When the concentration of sodium thiosulphate is higher, the higher the rate of reaction

Hypothesis: The higher the temperature of the reactant, the higher the rate of reaction

Hypothesis: The rate of decomposition of hydrogen peroxide increases when the amount of catalyst used is increased

Materials: 0.2 mol dm-3 sodium thiosulphate solution, 1.0 mol dm-3 sulphuric acid and distilled water

Materials: 0.1 mol dm-3 sodium thiosulphate solution and 1.0 mol dm-3 sulphuric acid

Materials: 0.2 mol dm-3 hydrogen peroxide nad manganese(VI) oxide

Apparatus: 10cm3 and 100cm3 measuring cylinders, 100cm3 conical flask, white paper marked with cross ‘X’ and stopwatch

Apparatus: conical flask, 10cm3 measuring cylinder, thermometer, stopwatch, white paper marked with cross ‘X’, wire gauze, tripod stand, and Bunsen burner.

Apparatus: measuring cylinder, conical flask, delivery tube, rubber stopper, retort stand, clamp and burette.

Procedure:1) Using ameasuring cylinder, measure and pour 45cm3 of 0.2

moldm-3 sodium thiosulphate, Na2S2O3 solution into a conical flask.

2) Place the conical flask on top of a piece of white paper with mark ‘X’.

3) Using another measuring cylinder, measure 5cm3 of 0.1 mol dm-3 sulphuric acid.

4) Pour the sulphuric acid quickly and carefully into the conical flask and start the stop watch immediately.

5) Swirl the mixture in the conical flask and start the stopwatch immediately.

6) Swirl the mixture in the conical flask a few times and place in back on the white paper.

7) Obeserve the mark ‘X’ vertically from the top through the solution.

8) Record the time t required for the mark ‘X’ to disappear from sight.

9) Repeat the experiment four more times using different volumes of 0.2 mol dm-3 sodium thiosulphate of different concentration.

Procedure:1)

Procedure:1) Using a measuring cylinder, 25 cm3 of 0.2 mol

dm-3 hydrogen peroxide is measured into a conical flask and 0.5 g of manganese(VI) oxide is added to the hydrogen peroxide.

2) The conical flask is immediately closed with a stopper fitted with delivery tube and the stopwatch is started simultaneously. The conical flask is swirled gently.

3) The total volume of oxygen gas given off is determined from the burette reading at intervals

of 12

minute for 4 minutes.

4) The experiment is repeated using 0.20 g of manganese(VI) oxide instead of 0.50 g of manganese(VI) oxide.

Tabulation of data: Tabulation of data: Tabulation of data:

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Experiment 19 (Chapter 11) SPM 2006 Experiment 20 (Chapter 12) Experiment 21 (Chapter 13) Aim: To compare the elasticity of vulcanized rubber and unvulcanized rubber

Aim:To investigate the effect of other metals on rusting

Aim:To determine the heat of combustion of various liquid alcohol

Problem statement:Is vulcanized rubber more elastic than unvulcanized rubber?

Problem statement:How do different types of metals in contact with iron affect rusting?

Problem statement:Does alcohol with more carbon atoms per molecule have a higher heat of combustion?

Variables: Manipulated: type of rubberResponding: lenght of rubber stripFixed (controlled): size of rubber strip, mass of weight

Variables: Manipulated: different metal in contact with ironResponding: presence of blue colouration//rusting Fixed (controlled): clean iron nails

Variables: Manipulated: different types of alcoholResponding: heat oof combustionFixed (controlled): volume of water, copper can

Hypothesis: vulcanized rubber is more elastic than unvulcanized rubber

Hypothesis: when a more electropositive metals is in contact with iron, the metal inhibits rusting. When a less electropositive is in contact with iron, the metal speeds up rusting

Hypothesis: the higher the number of carbon atoms in the molecules, the higher the heat of combustion

Materials: vulcanized rubber strip and unvulcanized rubber strip

Materials: 5 iron nails, 3cm magnesium ribbon, 3 cm copper strip, 3cm zinc strip, 3cm tin strip, 50cm3 hot jelly solution with a little potassium hexacyanoferrate(III) solution and phenolphthalein, sandpaper

Materials: 50cm3 of Methanol, Ethanol, Propanol, Butanol and 800cm3 water

Apparatus: retort stand and clamp, bulldog clip, metre rule, weights

Apparatus: 5 test tubes, test tube rack Apparatus: copper can, tripod stand, thermometer, 100cm3

measuring cylinder, spirit lamp, weighing balance, wooden block, wind shield.

Procedure:1) Hang both rubber strips using bulldog clips.2) Measure the initial lenght of both rubber strips.3) Hang 10g weight to the end of each rubber strip.4) Remove the weight and measure the lenght of

both rubber strips.5) Repeat steps 2 to 4 using 20g, 30g, 40g and 50g

weights to replace the 10g weights.6) Record the data.

Procedure:1) Clean all the five iron nails, magnesium ribbon,

strips of copper, zinc and tin with sandpaper.2) Coil four nails tightly with magnesium ribbon,

strips of cooper, zinc and tin each.3) Place all the iron nails in separate test tubes.4) Pour the same volume of hot jelly containing

potassium hexacyanoferrate(III) solution and phenolphthalein indicator int the test tubes in a test tube rack and leave them aside for a day.

5) Record the observation.

Procedure:1) Using a measuring cylinder, measure 200cm3 of water and

pour it into a copper can.2) Place the copper can on atripod stand.3) Measure the initial temperature of the water and record the

reading.4) Pour 50cm3 of methanol into a spirit lamp and then weight

the lamp and its content. Record the mass.5) Put the lamp and light up the wick of the lamp

immediately.6) Stir the water continuously until the temperature of water

increase about 30°C.7) Put off the flame and record the highest temperature

reached by the water.8) Weight the lamp and its content immediately and record its

reading.

9) Repeat steps 1 to 8 using other alcohol like Ethanol, Propanol, Butanol.

Tabulation of data: Tabulation of data: Tabulation of data:

7

Tabulation of data for experiment 21

Alcohol Methanol Ethanol Propan-1-ol Butan-1-olInitial temperature (°C)Highest temperature (°C)Rise in temperature of water (°C)Mass of spirit lamp before burning (g)Mass of spirit lamp after burning (g)Mass of alcohol burnt (g)

Tabulation of data for experiment 20

Test tube Pair of metals Intensity of the blue colour in the solution Intensity of pink colour in the solution inferenceA FeB Fe + ZnC Fe + CuD Fe + MgE Fe + Sn

Tabulation of data for experiment 19

Type of rubber Unvulcanised rubber Vulcanised rubberInitial length (cm)Stretched length (cm)Increase in length (cm)Length after removal of weight (cm)Difference in length (cm)

8

Tabulation of data for experiment 18

Time (s)Burette reading (cm3)Volume of hydrogen gas (cm3)

Tabulation of data for experiment 17

Set Temperature (°C) Time, t(s) 1/time (s-1)I.

II.III.IV.V.

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