pra percubaan p3 2014 set 1.docx

8/10/2019 PRA PERCUBAAN P3 2014 SET 1.docx

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REVISION PAPER 3 2014

QUESTION 11. Diagram 1.1 shows the apparatus set-up used in an experiment to compare the

hardness of bronze with its pure metal, copper.

Rajah 1.1menunjukkan susunan radas yang digunakan dalam satu eksperimenuntuk membandingkan kekerasan gangsa dengan logam tulennya, kuprum.

.The experiment was carried out according to the following steps:

Eksperimen itu dijalankan mengikut langkah-langkah berikut:Step 1 Cellophane tape was used to stick a steel ball bearing onto the copper

block.

Langkah 1 Pita selofen digunakan untuk melekatkan bebola keluli di atas bongkahkuprum.

Step 2 A one-kilogramweight was hung at the height of 50 cmabove the ballbearing as shown in Diagram 1.1

Langkah 2 Pemberat satu ki logramdigantung pada ketinggian 50 cmdi atas

bebola keluli itu seperti yang ditunjukkan dalam Rajah 1.1

Step 3 The weight was dropped so that it hit the ball bearing.

Langkah 3 Pemberat itu dijatuhkan supaya menghentam bebola keluli tersebut.

Step 4 The diameter of dent formed on the copper block was measured and thereading was recorded.

Langkah 4 Diameter lekuk yang terbentuk pada bongkah kuprum diukur danbacaannya direkodkan.

Step 5 Step 1 to step 4 were repeated by replacing the copper block with bronzeblock.

Langkah 5 Langkah 1 hingga 4 diulang dengan menggantikan bongkah kuprumdengan bongkah gangsa.

Diagram 1.1

Rajah 1.1

Ruler

String

Weight 1 kg

Steel ball

Block copper


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Diagram 1.2Rajah 1.2

(a) Measure the diameter of dents and record the readings in the spaces provided.

Ukur diameter lekuk dan catatkan bacaan pada ruang yang disediakan

[3 marks]

(b) Construct a table to record the diameter of dent formed on each copper block andbronze block

Bina satu jadual untuk merekod diameter lekuk yang terbentuk pada setiapbongkah kuprum dan bongkah gangsa.

[3 marks]

Copper block

BongkahBronze block

Bongkah

Diameter : . mm Diameter : . mm


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(c) (i) State oneobservation that can be obtained from this experiment.

Nyatakan satupemerhatian yang dapat diperoleh daripada eksperimen ini.

..........................................................................................................................................................

.........................................................................................................................................................[3 marks]

(ii) What is your inference based on your answer in (c) (i). Apakah inferens anda berdasarkan jawapan anda dalam (c)(i).

...........................................................................................................................................................

.........................................................................................................................................................[3 marks]

(iii) Explain your answer in c(ii)according to the arrangement of particles in thebronze and copper.

Terangkan jawapan anda dalam c(ii) berdasarkan susunan zarah-zarahdalam gangsa dan kuprum.

............................................................................................................................................................

...........................................................................................................................................................

............................................................................................................................................................[3 marks]

(d) For this experiment, state :

Bagi eksperimen ini, nyatakan :

(i) The manipulated variablePembolehubah dimanipulasikan

.............................................................................................................................


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(ii) The responding variable

Pembolehubah bergerak balas

.............................................................................................................................

(iii) The fixed variable

Pembolehubah dimalarkan

.............................................................................................................................[3 marks]

(e) State the hypothesis for the experiment.

Nyatakan hipotesis bagi eksperimen ini.

[3 marks]

(f) Based on Diagram 1.1 and 1.2, state the operational definition for the hardness of alloy.

Berdasarkan Rajah 1.2, nyatakan definisi secara operasi bagi kekerasan aloi.

...

[3 marks]

(g) The experiment is repeated by dropping one-kilogramweight at the height of 30cm.Predict the diameter of dent on copper block.

Eksperimen diulangi dengan menjatuhkan pemberat satu ki logrampadaketinggian 30cm.Ramalkan diameter lekuk di atas bongkah kuprum.

...

[3 marks]


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(h) The following is a list of substances:

Berikut ialah senarai bahan :

Classify these substances into alloy and pure metal.

Kelaskan bahan-bahan ini kepada aloi dan logam tulen.

AlloyAloiPure metalLogam tulen

[3 marks]

(i) Steel takes a longer time to corrode compared to iron. Explain.

Keluli memerlukan masa yang lebih panjang untuk berkarat berbanding dengan

besi. Terangkan.

...

...

...

[3 marks]

Antimony Bronze Copper

Antimoni Gangsa Kuprum

Brass Pewter Tin

Loyang Piuter Timah


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QUESTION 2Table 1.1 shows the observation in five test tubes used to investigate the effect of othermetals on rusting. A mixture of jelly solution, potassium hexacyanoferrate(III), K3Fe(CN)6solution and phenolphthalein were used as medium in each test tube.The observationswere recorded after one day.

Jadual 1.1 menunjukkan pemerhatian dalam lima buah tabung uji yang digunakan untukmenyiasat kesan logam lain ke atas pengaratan. Medium yang digunakan di dalam setiaptabung uji adalah campuran larutan agar, larutan kalium heksasianoferat(III), K3Fe(CN)6danfenolftalein. Pemerhatian direkod selepas satu hari.

Test tube 1Tabung uji 1





Table 1.1Jadual 1.1

Blue colourWarna biru

Iron nailPaku besi

High intensity of pink colourKeamatan warnamerah jambu tinggi

Iron nail coiled withmagnesium ribbon

Paku besi dililit denganpita magnesium

Iron nail coiled withcopper strip

Paku besi dililit dengankepingan kuprum

Iron nail coiled with zincstrip

Paku besi dililit dengankepingan zink

Iron nail coiled with tinstrip

Paku besi dililit dengankepingan timah

Low intensity of pink colourKeamatan warnamerah jambu rendah

High intensity of blue colourKeamatan warna biru tinggi

Low intensity of blue colourKeamatan warna birurendah


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(a) State the observation and inference for each test tube.Nyatakan pemerhatian dan inferens untuk setiap tabung uji.

Test tubeTabung uji

ObservationPemerhatian

InferenceInferens

1

2

3

4

5

(b) Based on this experiment, explain why there is a difference in observation betweentest tube 2 and 3.

Berdasarkan eksperimen ini, terangkan mengapa terdapat perbezaan pemerhatian diantara tabung uji 2 dan 3.

........................................................................................................................................

........................................................................................................................................

........................................................................................................................................[3 marks]

[3 markah]

(c) State the hypothesis for the experiment.

Nyatakan hipotesis bagi eksperimen tersebut.

.........................................................................................................................................

[3 marks]

[3 markah]


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(d) For this experiment, state:

Bagi eksperimen ini, nyatakan:

(i) The manipulated variable.

Pembolehubah dimanipulasi.

...................................................................................................................

(ii) The responding variable.

Pembolehubah bergerak balas.

......

(iii) The constant variable.

Pembolehubah dimalarkan.

.............................................................................................................................[3 marks]

(e) State the operational definition for the rusting of iron nail.

Nyatakan definisi secara operasi bagi pengaratan paku besi.

.........................................................................................................................................

.........................................................................................................................................[3 marks]

[3 markah]

(f) Magnesium, copper, zinc and tin were used in this experiment to investigate the effectof other metals on the rusting of iron nails. Classify the metals by completing Table1.2.

Magnesium, kuprum, zink dan timah digunakan dalam eksperimen ini untuk mengkajikesan logam lain ke atas pengaratan paku besi. Kelaskan logam-logam denganmelengkapkan Jadual 1.2.

Metals that inhibit rustingLogam yang

melambatkan pengaratan

Metals that speed up rustingLogam yang mempercepatkan

pengaratan

Table 1.2


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[3 marks](g) An iron nail was placed on a moist cotton to investigate the time taken for the iron nail

to rust completely. The observations are shown below.

Sebatang paku besi diletakkan di atas kapas lembap untuk mengkaji masa yangdiambil untuk paku besi itu berkarat dengan lengkap. Pemerhatian adalah ditunjuk

seperti di bawah.

After one daySelepas satu hari

After two daysSelepas dua hari

(i) State the relationship between the time taken and the amount of rust formed.

Nyatakan hubungan di antara masa yang diambil dan kuantiti karat yangterbentuk.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................[3 marks]

[3 markah]

(ii) The iron nail will take 5 days to rust completely in the water. Predict the timetaken for the iron nail to rust completely if it is placed in salt solution.

Sebatang paku besi mengambil masa 5 hari untuk berkarat dengan lengkap.Ramalkan masa yang diambil untuk paku besi itu berkarat dengan lengkap jikadiletakkan dalam larutan garam.

.................................................................................................................................[3 marks]

[3 markah]

Brown colourWarna perang

Brown colourWarna perang


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QUESTION 3

3.. Diagram 3 shows two methods of dissolving brown sugar to make sugar solution.

Rajah 3menunjukkan dua kaedah melarutkan gula perang untuk membuat larutan gula.

MethodKaedah After 5 minutesSelepas 5 minit

I

II

Diagram 3

Rajah 3A group a students discovered that it is faster to dissolve the brown sugar to make sugar solution

by using hot water rather than cold water.This is due to the difference in the temperature of the

water.

Sekumpulan pelajar mendapati bahawa lebih cepat untuk melarutkan gula perang menggunakanair panas berbanding air sejuk untuk membuat larutan gula. Ini disebabkan oleh perbezaan suhu

air.

By referring to the situation above, plan a laboratory experiment to investigate the effect of temperatureon the rate of reaction between acid and metal.

Merujuk pada situasi di atas, rancangkan satu eksperimen dalam makmal untuk mengkaji kesan suhuterhadap kadar tindak balas antara asid dan logsm.

Your planning should include the following aspects,

Hot water

Air panas

Cold water

Air sejuk

Brown solution

Larutan perang

Brown sugar crystal

Hablur gula perang

Paler brown solution

Larutan perang muda

Brown sugar crystal

Hablur gula perang

Brown sugar crystal

Hablur gula perang


11/26

Perancangan anda hendaklah mengandungi aspek-aspek berikut,

(a)Problem statement

Pernyataan masalah

(b)All the variablesSemua pemboleh ubah

(c )Hypothesis

Hipotesis

(d)Lists of materials and apparatus

Senarai bahan dan alat radas

(e)Procedure

Prosedur

(f)Tabulation of data

Penjadualan data

[17 marks]

QUESTION 4

Referring to the situation above, plan a laboratory experiment to compare the heat ofneutralisation between anamed strong acidwith sodium hydroxide solution and heat ofneutralisation between a named weak acidwith sodium hydroxide solution.

Merujuk kepada situasi di atas, rancangkan satu eksperimen dalam makmaluntuk membandingkan haba peneutralan antara suatu asid kuatyang dinamakan

dengan larutan natrium hidroksida dan haba peneutralan antara suatu asid lemahyang dinamakan dengan larutan natrium hidroksida.

Your planning should include the following aspects:

Perancangan anda hendaklah mengandungi aspek-aspek berikut:

(a) Problem statement

Pernyataan masalah

Neutralisation is a reaction between an acid and an alkalito form salt and water.

Peneutralan ialah satu tindak balas antara asid dengan alkali

untuk membentuk garam dan air.


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(b) All the variables

Semua pemboleh ubah

(c) Hypothesis

Hipotesis

(d) List of materials and apparatus

Senarai bahan dan radas

(e) Procedure

Prosedur

(f) Tabulation of data

Penjadualan data

[17 marks]

QUESTION 5

Diagram 5(a) and 5(b) below shows the apparatus set up to study the effects of metal X

and metal Y on the rusting of iron.

Rajah 5(a) dan 5(b) menunjukkan susunan alat radas untuk mengkaji kesan logam X dan logam Y

ke atas pengaratan besi

Diagram 5(a) Diagram 5(b)

Referring to the information in the diagram above,plan an experiment to investigate the effect of a

named Xand Y metalson the rusting of iron. Your planning should include the following aspects:

Merujuk kepada maklumat dari gambarajah di atas,rancangkan satu eksperimen untuk mengkaji

kesan logam X dan logam Y yang dinamakanke atas pengaratan besi.Perancangan anda

hendaklah mengandungi aspek-aspek berikut:


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(a) Problem statement

Pernyataan masalah

(b) All the variables

Semua pemboleh ubah

(c) Hypothesis

Hipotesis

(d) List of materials and apparatus

Senarai bahan dan alat radas

(e) Procedure

Prosedur

(f) Tabulation of data

Penjadualan data[17 marks]


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ANSWER QUESTION NO 1

Question Rubric Score

1(a) Able to state the diameter of the dents accurately

Sample answer:

Block X : 30Block Y : 25

3

Able to state any reading accurately with one or more decimal

place

2

Able to state the diameter of the dent in cm(2.5 and 3.0) 1

No response or wrong response 0


1(b) Able to construct a table to record the diameter of dents formed on

block X and Y accuratelySample answer:

Material/Block Diameter of the dent / mm

X 30

Y 25

3

Able to construct a table to record the diameter of dents formed on

block X and Y accurately without unit

2

Able to construct a table to record any one of diameter of dents

formed on block X and Y

1



1(c)(i) Able to state all the observations correctly

Sample answers:

The size / diameter of dents on copper block are bigger than the

size / diameter of dents on bronze block.

3

Able to state the observation without comparison

-The diameter formed on copper block is big

2

Able to give an idea of the observation-the dent is formed

1



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1(c)(ii) Able to state all the inferences correctly

Sample answers:

Bronze is harder than copper // Copper is less harder thanbronze

3

Able to state the inferencesSample answer:

Alloy is harder than its pure metal

2

Able to give the idea od inferences

Sample answer:

Alloy is harder/hard

1


Question Rubric Score1(c)(iii) Able to state the arrangement of particles in the materials

correctly

Sample answers:In bronze,

1.tin atoms and copper atoms are of different sizes

2.the presence of tin atoms disturb the orderly arrangement ofcopper atoms

3.the layers of copper atoms/ atoms difficult to slide when force is

applied

3

Able to state any two of statements from score 3 2Able to state any one of the statements from score 3 1

No respble to stonse or wrong response 0


1(d) Able to state all the three variables correctly

Sample answer:

Manipulated variable:

Different types of materials/block//copper and bronze

Respondingvariable: Size / diameter of dent// hardness of the

blockConstant variable:

Size / diameter of steel ball bearing // height of the weight // mass

of the weight

3

Able to state any two variables correctly 2

Able to state any one variable correctly 1



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1(e) Able to state the relationship between the manipulated variable

and the responding variable with direction.

Sample answer:

Bronze is harder than copper // Copper is less harder than bronze//Bronze has smaller size / diameter of dent than copper// alloy isharder than its pure metal

3

Able to state the relationship between the manipulated variable

and responding variable.

Sample answer:

When the size / diameter of dent is smaller, the material is harder

2

Able to state the idea of hypothesis

Sample answer:Different materials have different diameter/size of the dent

1



1(f) Able to state the operational definition for alloy accurately

Sample answer:When a force is applied, the material that has smaller dent is the

harder // the hardness depend on the diameter of the dent formed

when weight is hit on the surface of the block/when force is

applied

3

Able to state the operational definition for alloy correctly

Sample answer:The material that has smaller size / diameter of dent is the harder.

2

Able to state an idea for the potential differenceSample answer:

Bronze is alloy

1



1(g) Able to predict the diameter of the dent correctly

Sample answer:State one number in range between 18 mm to 30 mmm//1.8cm to 3.0 c

3

Between 25mm-30mm 2

less than 30 mm 1



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1(h) Able to classify allos and pure metals correctly

Sample answer:

Alloys Brass, bronze, pewter

Pure metals Copper, antimony, tin

3

Able to classify two alloys and two pure metals //all alloys or pure

metals correctly

2

Able to classify one alloy or one pure metal correctly 1



1(i) Able to explain the relationship between the time for steel tocorrode accurately

Sample answer:The present of carbon atom in steel will reduce /slow down theformation of iron (III) oxide layer/oxide layer

3

Able to explain the relationship between the time for steel to

corrode correctly:

Sample answer:The present of carbon atom prevent the steel from easily rust//

Alloying prevent the formation of oxide layer on the surface of

steel//When iron expose to air, the oxide layer is formed on the

surface of iron.

2

Able to state an ideaof the relationship between the time correctlySample answer:

Steel not easier to corrode//steel is protected by a layer

substance//steel is an alloy

1



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ANSWER

QUESTION 2

Question Mark Scheme Marks

1(a) Able to state 5 correct observations.

Able to state 3-4 correct observations.Able to state 1-2 correct observations.

Sample answer

Test

tubeObservation

1 blue colour /solutions

2 High intensity of pink colour/ solutions

3 High intensity of blue colour /solutions

4 Low intensity of pink colour/ solutions

5 Low intensity of blue colour /solutions

Able to state 5 correct inferences.

Able to state 3-4 correct inferences.

Able to state 1-2 correct inferences.

Sample answer

Testtube

Inference

1 Iron(II) / Fe ions formed / produced in the solutions //

Iron / Fe rusted/corroded/oxidised

2

Iron(II) / Fe+ions are not formed /produced in the

solutions //

Iron / Fe does not rust/ corrode/oxidised

Magnesium/Mg rusted/corroded /oxidised

3Iron(II) / Fe

+ions formed / produced in the solutions //

Iron / Fe rusted/ corroded/ oxidised

4

Iron(II) / Fe ions are not formed /produced in thesolutions //

Iron / Fe does not rust/ corrode/oxidised //

Zinc/Zn rusted/ corroded / oxidised

5 Iron(II) / Fe ions formed / produced in the solutions //Iron / Fe is rusted / corroded/ oxidised

3

21

3

21


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Mark Scheme Marks

1(b) Able to explain a difference in observation correctly between

test tube 2 and 3

Sample answer

Iron/Ferum/Fe in test tube 2 does not rust/ corrode/ oxidised because

ferum is in contact with a more electropositive metal, but

iron/Ferum/Fe in test tube 3 rusts/ corrodes/ is oxidised becauseferum is in contact with a less electropositive metal. //

In test tube 2, magnesium is more electropositive than ferum/iron

and and in test tube 3, copper is less electropositive the ferum/iron.

3

Able to explain a difference in observation between test tube 2

and test tube 3 incompletely.

Sample answer

Iron/Ferum/Fe in test tube 2 does not rust/ corrode/ oxidised, but

iron/Ferum/Fe in test tube 3 rusts/ corrodes/ is oxidised.

2

Able to state any idea of difference in observation.

Sample answer

Iron/Ferum/Fe/nail/metal does not rust / corrode/ oxidised //

Iron/Ferum/Fe/nail/metal rusts / corrodes/ is oxidised

1



20/26


1(c) Able to state the hypothesis correctly.

Sample answer

When a more/less electropositive metal is in contact withiron/ferum/Fe, the metal inhibits/(speeds up) rusting/corrosion of

iron //

When a more/less electropositive metal is in contact withiron/ferum/Fe, rusting of iron/ferum/Fe is faster/slower //

If the metal in contact with iron is higher/lower than iron/ferum/Fein electrochemical series, the rusting/corrosion of iron isslower/faster //

The higher/lower the metal in contact with iron in electrochemicalseries/ than iron/ferum/Fe, the rusting/corrosion of iron/ferum/Fe is

slower/faster

3

Able to state the hypothesis less accurately.

Sample answer

When a more/less electropositive metal, the metal inhibits/(speedsup) rusting/corrosion of iron //

If the metal in contact with iron is higher than iron/ferum/Fe in

reactivity series, the rusting/corrosion of iron is slower/faster //

The rusting of iron/ferum/Fe is faster/slower, if a more/less

electropositive metal is in contact with iron/ferum/Fe

2

Able to give an idea of hypothesis.

Sample answer

Different metal in contact with iron, will cause iron to rust //

Metal can cause iron to rust.

1



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1(d) Able to state all the variables in this experiment correctly.

Sample answer

(i) Manipulated variables:Type/different metal // position of metal in electrochemical

series

(ii) Responding variable:

Rusting / corrosion // presence of blue/pink colour

(iii) Constant variable:Size/mass of iron nail // type of nail // clean iron nails //

temperature // medium in which the iron nail are kept

3

Able to state any two of the variables in this experiment

correctly.

2

Able to state any one of the variables in this experiment

correctly.

1



22/26


1(e) Able to state the operational definition for the rusting of iron

nail correctly.

Sample answerBlue colouration indicates rusting occurs.//

Rusting occurs when iron nail is in contact with copper/tin /lesselectropositive metal and form blue colouration in potassium

hexacyanoferrate(III) solution

3

Able to state the operational definition for the rusting of iron

nail less accurately

Sample answer:

Rusting occurs when iron nail is in contact with copper/tin /lesselectropositive metal.

2

Able to state any idea of operational definition.

Sample answer:

Rusting occurs when the colour of solution changes. //

Rusting occurs

1



23/26


1(f) Able to classify all the metals correctly.

Sample answer

Metals that inhibit rusting Metals that speed up rusting

Magnesium/MgZinc/Zn

Tin/SnCopper/Cu

3

Able to classify at least three metals correctly. 2

Able to classify any one of the metals correctly. 1


1(g)(i) Able to state the relationship between the time taken and the

amount of rust formed correctly.

Sample answer

The longer the time taken, the greater/bigger/larger the rust formed// The longer the time taken, more rust is formed // The rust formed

is greater/bigger/larger, when the time taken is longer.

3

Able to state the relationship between the time taken and the

amount of rust formed less accurately.

Sample answer:

The rust formation is directly proportional with time. //

The rust formed is greater/bigger/larger after two days compared to

one day. //

The rust formed in two days is more than in one day [vice-versa

2

Able to state any idea of the relationship between the time taken

and the amount of rust.

Sample answer:

The rust formed in two days is greater/bigger/larger. //

The rust formed in one day is lesser/smaller

1




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1(g)(ii) Able to predict the time taken for the iron nail to completely

rust correctly.

Answer

Less than 5 days

3

Able to predict the time taken for the iron nail to completely

rust less accurately

Answer:

5 days

2

Able to give an idea of the time taken.

Sample answer:

More than 5 days

1


QUESTION 3

(a)Does the rate of reaction between acid and metal increase when temperature of acid increases?(b)MV: temperature of acid

RV: rate of reaction

CV: volume and concentration of acid//mass of zinc

(c )When the temperature of acid increases, the rate of reaction between acid and metalincreases.

(d)Materials: 1 g of zinc powder, 50 cm30.5 mol dm

-3Hydrochloric acid

Apparatus: beaker 250 cm3, stopwatch,measuring cylinder,weighing balance,thermometer.

(e) 1).50 cm30.5 mol dm

-3hydrochloric acid is measured and poured into a beaker.

2)The temperature of the acid is recorded.3)1.0 g zinc powder is added into the beaker.

4)Immediately , the stopwatch is started.5)The time is recorded until there is no more bubbles produced.6)Step 1 to 5 is repeated by heating the acid to 40, 50

0C.

(f) Temperature of acid( C) Time taken when there is no bubbles formed(s)

Room temperature

40

50


25/26

ANSWER: QUESTION 4

(a)Does heat of neutralisation of strong acid is higher than heat of neutralisation of weak acid

when react with sodium hydroxide?

(b) Manipulated variable : Types of acids//strength of acids

Responding variable : Heat of neutralization//heat change

Constant variable : Volume and concentration of acid // polystyrene cup

(c )Strong acid produce higher/lower heat of neutralization than weak acid when react with

sodium hydroxide solution

(d)Materials

Hydrochloric acid and ethanoic acid [0.5 2.0] mol dm-3

,

sodium hydroxide solution [0.52.0] mol dm-3

ApparatusPolystyrene cup, measuring cylinder, thermometer .

(e)Procedure:

1. 25 cm3of sodium hydroxide solution 1.0 mol dm-3 is measured and poured into a

polystyrene cup.

2. The initial temperature of the solution is recorded

3. 25 cm3of hydrochloric acid 1.0 mol dm-3 is measured

4. The initial temperature of the acid is recorded

5. The hydrochloric acid is poured into the sodium hydroxide solution

6. The mixture is stirred using a thermometer and the highest temperature is recorded

7. The experiment//Step 1 to 6 is repeated using ethanoic acid

(a) Data:

Acid Hydrochloric

acid

Ethanoic

acid

Initial temperature ofNaOH solution/alkali (

oC)

Initial temperature ofacid solution (

oC)

Highest temperature of

the mixture (oC)


26/26

ANSWER : QUESTION 5

Problem statement: Does metal X/magnesium metal prevent iron from rusting while

metal Y/copper metal makes the iron to rust?

Variables:

MV: types of metals contact with iron

RV: rusting of iron

CV: type of nail

Hypothesis:

When the more electropositive metal/ magnesium metal contact with iron, the iron

is prevent from rusting while when the less electropositive metal/copper metal

contact with iron, iron rusting.

Materials:Iron nails,magnesium stripe,copper stripe,potassium

hexacyanoferrate(III) solution, phenolphthalein, hot jelly solution

Apparatus: test tube,test tube rack, sand paper

Procedure:

1) Magnesium strip, copper strip and iron nails are cleaned with sand paper.

2) One iron nails is coiled with magnesium

pra percubaan p3 2014 set 1.docx

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