Paper 3 Chemistry Form 4 Final Exam

CONFIDENTIAL 1 4541/3

Chemistry Name :_________________________________4541/3October 2014 I/C No. :_________________________________1 Hour 30 minutes

Class. :_________________________________

FINAL EXAMINATION

CHEMISTRYPaper 31 HOUR 30 MINUTES

DO NOT OPEN THIS BOOKLET UNTIL INSTRUCTED

1. This question paper consists of two questions: Question 1 and Question 2.

2. Answer all the questions. You may use equations, diagrams, tables, graph, and other suitable method to explain your answer.

3. The diagrams in the questions are not drawn to scale unless stated.

Question Full marks

Mark obtained

1 33

2 17

Total 50

4. The marks allocated for each question or subpart of a question is shown in brackets.

5. You may use a non-programmable scientific calculator.

6. You are advised to spend 45 minutes to answer Question 1 and 45 minutes for Question 2.

Prepared by : Mrs. Wan Nurul Aini Wan Nor YuhaidiChecked by : Mr. Tan K. K.Approved by : Mrs. Hariah Muhi

This question paper consists of 6 printed pages

4541/3 [Please turn overCONFIDENTIAL

SECONDARY 4


Answer all questions.

1 Diagram 1.1 shows the apparatus set – up for an experiment to construct the electrochemical series based on the potential difference between pairs of metals in asimple voltaic cell.Copper plate is paired with zinc, lead, iron, aluminium and magnesium metals inCell I, Cell II, Cell III, Cell IV and Cell V respectively. In each cell, copper acts asthe positive terminal.

Diagram 1.1

Diagram 1.2 shows the voltmeter readings of each cell.

Cell I: Cu – Zn

Voltmeter reading: ____________V

Cell II: Cu – Pb




Cell III: Cu – Fe


Cell IV: Cu – Al

Voltmeter reading: ____________VCell V: Cu - Mg

Voltmeter reading: ______________V

Diagram 1.2

(a) Record the voltmeter readings of each cell in the spaces provided in Diagram1.2.

[3 marks]

(b) Complete the table to record the cell voltage and negative terminal in each ofthese cells.

Cell Pair of metals Negative terminal Cell voltage/VI Zink – CopperII Lead – CopperIII Iron – CopperIV Aluminium – CopperV Magnesium - Copper

[3 marks]



(c) State three observations and the corresponding inferences in Table 1.1. Theobservations should not include the deflection of voltmeter needle.

Observation InferenceNegative terminal

Positive terminal

Colour of the solution

[6 marks]

(d) State one hypothesis for this experiment.………………………………………………………………………………………

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

(e) For this experiment, state the:(i) manipulated variable : ……………………………………………………...(ii) responding variable : ……………………………………………………...(iii) constant variable : ……………………………………………………...

[3 marks]

(f) State the operational definition for the position of metals in theelectrochemical series.

………………………………………………………………………………………

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

(g) Arrange the six metals in descending order of electropositivity.………………………………………………………………………………………



[3 marks]

(h) (i) The experiment is repeated using another copper plate to pair with thecopper plate. Predict the voltmeter reading.

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

(ii) Explain the answer in 1(h)(i).…………………………………………………………………………………

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

(i) Classify the ions present in the electrolyte of copper (II) sulphate in thisexperiment by completing Table 1.2.

Anions Cations(i) (iii)

(ii) (iv)

[3 marks]



2 Diagram 2 shows the apparatus set – up for titration of 25.0 cm3 of 1.0 mol dm-3 ofpotassium hydroxide, KOH solution with dilute hydrochloric acid, HCl.Phenolphthalein is used as an indicator.

Diagram 2

Based on this situation, plan one experiment in the laboratory to determine theconcentration of hydrochloric acid by finding the end point of titration. Your planning should include the following aspects.

(a) Aim of the experiment (b) Statement of the hypothesis (c) All the variables (d) List of substances and apparatus (e) Procedure of the experiment (f) Tabulation of data

[17 marks]

END OF QUESTION PAPER


Dilute hydrochloric acid

Potassium hydroxide + phenolphthalein


ANSWER SCHEME CHEMISTRY FINAL EXAMINATION SECONDARY 4 (PAPER 3)


Paper 3 Chemistry Form 4 Final Exam

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