O LevelChemistryCambridge (CIE)Exam Questions9. Metals9.1 Properties of Metals

Properties of Metals (Cambridge (CIE) O Level Chemistry): Alternative to Practical Questions

Exam code: 5070

3 hours33 questions

Select a download format for 9.1 Properties of Metals

Scroll for more

Select an answer set to view for
9.1 Properties of Metals

1a
5 marks

A student investigated the temperature change produced when equal lengths of magnesium ribbon reacted with excess dilute sulfuric acid of different concentrations (labelled solutions A, B, C, D and E).

Five experiments were carried out.

Experiment 1

Using a measuring cylinder, 20 cm3 of sulfuric acid solution A was poured into a beaker. The initial temperature of the solution was measured. A length of magnesium ribbon was added to the solution and stirred. The highest temperature reached was measured.

Experiment 2

Experiment 1 was repeated using solution B instead of solution A. The initial and highest temperatures were measured as before.

Experiment 3

Experiment 1 was repeated using solution C. The initial and highest temperatures were measured.

Experiment 4

Experiment 1 was repeated using solution D. The initial and highest temperatures were measured.

Experiment 5

Experiment 1 was repeated using solution E. The initial and highest temperatures were measured.

Use the thermometer diagrams in the table, to record the initial and highest temperatures in each experiment.

solution of sulfuric acid

thermometer diagram

initial temperature / oC

thermometer diagram

highest temperature / oC

change in temperature / oC

A

A thermometer with a vertical scale numbered 20, 25 and 30, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.
A thermometer with a vertical scale numbered 30, 35 and 40, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.

B

A thermometer with a vertical scale numbered 20, 25 and 30, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.
A thermometer with a vertical scale numbered 30, 35 and 40, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.

C

A thermometer with a vertical scale numbered 20, 25 and 30, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.
A thermometer with a vertical scale numbered 30, 35 and 40, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.

D

A thermometer with a vertical scale numbered 20, 25 and 30, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.
A thermometer with a vertical scale numbered 25, 30 and 35, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.

E

A thermometer with a vertical scale numbered 20, 25 and 30, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.
A thermometer with a vertical scale numbered 20, 25 and 30, with smaller unlabelled divisions between the numbers, and a shaded liquid column rising from the bulb at the base.

Work out the temperature change for each experiment and record the values in the table.

How did you do?

1b
4 marks

Draw a labelled bar chart of the results for Experiments 1, 2, 3, 4 and 5 on the grid below.

 

How did you do?

1c
1 mark

Use the results and observations to answer the following questions.

What type of chemical reaction occurs when magnesium reacts with dilute sulfuric acid?

How did you do?

1d
2 marks

i)

Which Experiment produced the largest temperature change?

 

[1]

 

ii)

Suggest why this Experiment produced the largest temperature change.

 

[1]

How did you do?

1e
3 marks

Predict the effect on the temperature changes that would happen if

 

i)

equal masses of magnesium powder were used in the Experiments.

 

[1]

 

ii)

40cm3 of dilute sulfuric acid was used in Experiment 1.

 

[1]

 

iii)

Explain your answer to (e)(ii).

 

[1]

How did you do?

1f
1 mark

Give one possible source of experimental error in this investigation.

How did you do?

2a
1 mark

A student investigated the reactions of three metals with dilute sulfuric acid.

25 cm3 of dilute sulfuric acid was measured into each of three test tubes. 0.1 g of a different powdered metal was added to each tube.

The observations are shown.

metal

observations

P

rapid bubbles, all the metal disappeared within 20 s

Q

slow bubbles, some metal remained after 5 minutes

R

no bubbles, the metal was unchanged after 5 minutes

Name the piece of apparatus the student should use to measure 25 cm3 of dilute sulfuric acid accurately.

How did you do?

2b
2 marks

The bubbles seen in the tubes containing metal P and metal Q are the same gas.

Name this gas.

Describe a test that would confirm its identity.

How did you do?

2c
2 marks

State two variables the student controlled in this investigation.

How did you do?

2d
2 marks

The student used 0.1 g of each metal as a powder, rather than using one small piece of each metal.

Explain why this makes the comparison between the three metals more reliable.

How did you do?

2e
2 marks

The student repeats the investigation using 0.1 g of metal P as a single lump instead of as a powder.

Predict the effect on the time taken for the metal to disappear.

Explain your answer.

How did you do?

2f
2 marks

Give one source of error in this investigation.

Suggest an improvement that would reduce it.

How did you do?

2g
1 mark

State the conclusion the student can draw about metal R from these observations.

How did you do?

3
6 marks

Plan an investigation to compare how quickly magnesium and zinc react with dilute hydrochloric acid.

You are provided with magnesium ribbon, zinc granules, dilute hydrochloric acid and the apparatus normally found in a school laboratory.

Your plan should include:

  • the apparatus you would use

  • the method and the measurements you would make

  • how you would make the comparison a fair one

  • how you would use your results

No other chemicals should be used.

How did you do?

4a
1 mark

A student heated 2.00 g of copper powder in an open crucible.

The crucible was heated, allowed to cool and reweighed. This was repeated until the mass no longer changed.

The results are shown.

heating

mass of solid / g

1

2.35

2

2.48

3

2.50

4

2.50

Name the piece of apparatus the student used to find the mass of the solid.

How did you do?

4b
1 mark

Calculate the increase in the mass of the solid during the investigation.

How did you do?

4c
2 marks

Explain why the mass of the solid increased during the investigation.

How did you do?

4d
2 marks

Explain why the student heated, cooled and reweighed the solid several times instead of heating it once.

How did you do?

4e
2 marks

A second student carries out the same investigation but keeps a tightly fitting lid on the crucible throughout the heating.

Explain the effect this would have on the final mass of the solid.

How did you do?

4f
1 mark

State which heating the results show the reaction was complete by, and give the reason for your answer.

How did you do?

4g
1 mark

Suggest one reason why a student carrying out this investigation might obtain a final mass lower than expected.

How did you do?

5a
2 marks

A student determined the melting point of a solid, X.

A small sample of X was packed into a capillary tube. The tube was attached to a thermometer and placed in a beaker of oil. The oil was heated slowly and stirred throughout.

Thermometer A shows the temperature at which the solid first began to melt.

Thermometer B shows the temperature at which the solid had completely melted.

Fig. 2.1

Two thermometer diagrams side by side, labelled thermometer A and thermometer B. Each is a narrow vertical tube with a round bulb at the bottom and a shaded liquid column rising from the bulb. A scale beside each tube runs from 45 at the bottom to 60 at the top, with a short mark at every unit and a longer numbered mark every five units, headed temperature in degrees Celsius.

Record the two temperatures shown in Fig. 2.1.

How did you do?

5b
1 mark

Calculate the melting range of X.

How did you do?

5c
1 mark

A second student recorded the same two readings as 52 °C and 54.5 °C.

State which of these values is recorded to the wrong degree of precision, and give the value as it should have been recorded.

How did you do?

5d
2 marks

A pure substance melts over a range of less than 1 °C.

The student claims that X is a pure substance that melts at 53 °C.

Explain why the results do not support this claim.

How did you do?

5e
2 marks

Explain why the oil was stirred throughout the heating.

How did you do?

5f
2 marks

Suggest one improvement the student could make to obtain a more accurate melting point.

Explain how it would help.

How did you do?