Cambridge IGCSE Chemistry - 0620 - Supplement Paper 2 2012 Summer Zone 3

Which diagram shows the process of diffusion?
Diagrams A, B, C, and D show different arrangements of atoms and arrows indicating direction of diffusion. Each diagram consists of two rectangular boxes with varied arrangements of two types of atoms, distinguished by color as shown in the key.

A student investigates how the concentration of an acid affects the speed of reaction with a 0.5 g mass of magnesium at 30°C.
The student has a beaker, concentrated acid, water and the apparatus below.

P a balance
Q a clock
R a measuring cylinder
S a thermometer

Which pieces of apparatus does the student use?
A P, Q and R only
B P, Q and S only
C Q, R and S only
D P, Q, R and S

Which method is most suitable to obtain zinc carbonate from a suspension of zinc carbonate in water?
A crystallisation
B distillation
C evaporation
D filtration

The electronic structures of atoms P and Q are shown.

P and Q react to form an ionic compound.
What is the formula of this compound?
A. PQ₂ B. P₂Q C. P₂Q₆ D. P₆Q₂

An element Y has the proton number 18.
The next element in the Periodic Table is an element Z.
Which statement is correct?
A Element Z has one more electron in its outer shell than element Y.
B Element Z has one more electron shell than element Y.
C Element Z is in the same group of the Periodic Table as element Y.
D Element Z is in the same period of the Periodic Table as element Y.

Which atom has twice as many neutrons as protons?
A: $^1_1H$
B: $^2_1H$
C: $^3_1H$
D: $^4_2He$

Which is a simple covalent molecule?
[Table_1]
| | conducts electricity | | volatile | |---|----------------------|------------|----------| | | when solid | when molten| | | A | ✔ | ✔ | ✖ | | B | ✔ | ✖ | ✔ | | C | ✖ | ✔ | ✖ | | D | ✖ | ✖ | ✔ |

The equation for the reaction between magnesium and dilute sulfuric acid is shown.
$$\text{Mg + H}_2\text{SO}_4 \rightarrow \text{MgSO}_4 + \text{H}_2$$
$M_r$ of $\text{MgSO}_4$ is 120
Which mass of magnesium sulfate will be formed if 12 g of magnesium are reacted with sulfuric acid?
A 5g
B 10g
C 60g
D 120g

The diagrams show the structures of two forms, P and Q, of a solid element.

What are suitable uses of P and Q, based on their structures?
[Table_1]

Winston Churchill, a British Prime Minister, had his false teeth electroplated with gold.
The teeth were coated with a thin layer of carbon and were then placed in the apparatus shown.

Which row is correct?
[Table_1]

The apparatus shown is used to measure the speed of a reaction.

Which equation represents a reaction where the speed can be measured using this apparatus?
A Mg(s) + 2HCl(aq) \rightarrow MgCl_2(aq) + H_2(g)
B HCl(aq) + NaOH(aq) \rightarrow NaCl(aq) + H_2O(l)
C Fe(s) + CuSO_4(aq) \rightarrow Cu(s) + FeSO_4(aq)
D 2Na(s) + Br_2(l) \rightarrow 2NaBr(s)

The diagram shows the reaction between zinc oxide and dilute hydrochloric acid.

Which terms describe the reaction?

[Table_1]

The diagram shows that two gases are formed when concentrated hydrochloric acid is electrolysed using inert electrodes.
Which row correctly describes the colours of the gases at the electrodes?

[Table_1]

A : anode (+ve) colourless, cathode (–ve) colourless
B : anode (+ve) colourless, cathode (–ve) yellow-green
C : anode (+ve) yellow-green, cathode (–ve) colourless
D : anode (+ve) yellow-green, cathode (–ve) yellow-green

A gas is escaping from a pipe in a chemical plant.
A chemist tests this gas and finds that it is alkaline.
What is this gas?
A. ammonia
B. chlorine
C. hydrogen
D. sulfur dioxide

The element vanadium, V, forms several oxides.
In which change is oxidation taking place?
A) $\text{VO}_2 \rightarrow \text{V}_2\text{O}_3$
B) $\text{V}_2\text{O}_5 \rightarrow \text{VO}_2$
C) $\text{V}_2\text{O}_3 \rightarrow \text{VO}$
D) $\text{V}_2\text{O}_3 \rightarrow \text{V}_2\text{O}_5$

Dilute hydrochloric acid is added to a solid, S.
A flammable gas, G, is formed. Gas G is less dense than air.
What are S and G?

[Table_1]

Table:
| | solid S | gas G |
|-------|-----------------|----------------|
| A | copper | hydrogen |
| B | copper carbonate| carbon dioxide |
| C | zinc | hydrogen |
| D | zinc carbonate | carbon dioxide |

The results of three tests on a solution of compound X are shown in the table.

[Table_1]
test | result
aqueous sodium hydroxide added | white precipitate formed, soluble in excess
aqueous ammonia added | white precipitate formed, insoluble in excess
acidified silver nitrate added | white precipitate formed

What is compound X?
A. aluminium bromide
B. aluminium chloride
C. zinc bromide
D. zinc chloride

The graph shows how the pH changes as an acid is added to an alkali.
acid + alkali → salt + water
Which letter represents the area of the graph where both acid and salt are present?

Which properties of the element titanium, Ti, can be predicted from its position in the Periodic Table?
[Table_1]
\begin{array}{|c|c|c|c|c|} \hline & \text{can be used} & \text{conducts electricity} & \text{has low density} & \text{forms coloured} \\ & \text{as a catalyst} & \text{when solid} & & \text{compounds} \\ \hline A & \checkmark & \checkmark & \times & \checkmark \\ B & \checkmark & \checkmark & \checkmark & \times \\ C & \checkmark & \times & \checkmark & \checkmark \\ D & \times & \checkmark & \checkmark & \checkmark \\ \hline \end{array}

The diagram shows a section of the Periodic Table.

Which element is described below?

'A colourless, unreactive gas that is denser than air.'

Element X is below iodine in the Periodic Table.
Which row correctly shows the physical state of element X at room temperature and its reactivity compared with that of iodine?

[Table_1]

Which property is shown by all metals?
A. They are extracted from their ores by heating with carbon.
B. They conduct electricity.
C. They form acidic oxides.
D. They react with hydrochloric acid to form hydrogen.

Five elements have proton numbers 10, 12, 14, 16 and 18.
What are the proton numbers of the three elements that form oxides?
A 10, 12 and 14
B 10, 14 and 18
C 12, 14 and 16
D 14, 16 and 18

Metal X reacts violently with water.
Metal Y reacts slowly with steam.
Metal Z does not react with dilute hydrochloric acid.
What is the correct order of reactivity of these metals, most reactive first?
A. X → Y → Z
B. X → Z → Y
C. Z → X → Y
D. Z → Y → X

Which statement about the extraction of iron from its ore is correct?
A. Iron is more difficult to extract than zinc.
B. Iron is more difficult to extract than copper.
C. Iron is easy to extract because it is a transition metal.
D. Iron cannot be extracted by reduction with carbon.

Which statement about the uses of metals is correct?
A Aluminium is used in the manufacture of aircraft as it has a high density.
B Aluminium is used to make food containers as it conducts electricity.
C Stainless steel for cutlery is made by adding other elements to iron.
D Stainless steel is used to make chemical reactors as it corrodes readily.

Fertilisers need to supply crops with three main elements. Which compound contains all three of these elements? A $\text{H}_3\text{PO}_4$ B $\text{KNO}_3$ C $\text{NH}_4\text{K}_2\text{PO}_4$ D $\text{NH}_4\text{NO}_3$

Some uses of water are listed.
1 for drinking
2 in chemical reactions
3 in swimming pools
4 in washing
For which uses is it necessary to chlorinate the water?
A 1 and 2
B 1 and 3
C 2 and 4
D 3 and 4

Which is a use of oxygen?
A. filling balloons
B. filling light bulbs
C. food preservation
D. making steel

Coal is a fossil fuel. Which gas is \textbf{not} formed when coal burns?
A. carbon dioxide
B. carbon monoxide
C. methane
D. sulfur dioxide

Air containing an acidic impurity was neutralised by passing it through a column containing substance X.

What is substance X?
A. calcium oxide
B. sand
C. sodium chloride
D. concentrated sulfuric acid

A new planet has been discovered and its atmosphere has been analysed.



The table shows the composition of the atmosphere.

[Table_1: { 'gas': ['carbon dioxide', 'nitrogen', 'oxygen'], 'percentage by volume': [4, 72, 24] }]

Which gases are present in the atmosphere of the planet in a higher percentage than they are in the Earth's atmosphere?

A carbon dioxide and oxygen
B carbon dioxide only
C nitrogen and oxygen
D nitrogen only

The structure of a compound is shown. Which functional groups are present in this compound? [Table_1]

Gas X is a waste gas from digestion in animals.
Gas Y is formed when gas X is burnt with a small amount of oxygen.
Gas Z is formed when gas X is burnt with an excess of oxygen.

What are X, Y and Z?

[Table_1]

Which fraction from the fractional distillation of petroleum does not match its correct use?

\[\begin{array}{|c|c|}\hline \text{ } & \text{ } \\ \textbf{fraction} & \textbf{use} \\ \hline \textbf{A} & \text{fuel oil} & \text{domestic heating} \\ \textbf{B} & \text{kerosene} & \text{jet fuel} \\ \textbf{C} & \text{naphtha} & \text{making roads} \\ \textbf{D} & \text{refinery gas} & \text{for heating and cooking} \\ \hline \end{array}\]

When a long chain hydrocarbon is cracked, the following products are produced.
1. $\text{C}_3\text{H}_8$
2. $\text{C}_2\text{H}_4$
3. $\text{C}_3\text{H}_6$
4. $\text{C}_2\text{H}_6$
Which products would decolourise bromine water?
A. 1 and 4
B. 2 and 3
C. 2 only
D. 3 only

The diagram shows apparatus used to separate petroleum into four fractions. Which fraction contains the smallest hydrocarbon molecules?

[Table_1]
fraction | boiling point range / °C
A | up to 70
B | 70 to 120
C | 120 to 170
D | over 170

PVA is a polymer. The monomer has the structure shown.

To which homologous series does this compound belong?
[Table_1]

Ethanol is an important chemical produced by the ......1...... of ......2....... .
Which words correctly complete gaps 1 and 2?

[Table_1]

Table:
| | 1 | 2 |
|---|------------|---------|
| A | combustion | ethane |
| B | combustion | glucose |
| C | fermentation | ethane |
| D | fermentation | glucose |

Which equation represents incomplete combustion of ethane?
A. $\text{C}_2\text{H}_6 + \text{O}_2 \rightarrow 2\text{CO} + 3\text{H}_2$
B. $\text{C}_2\text{H}_6 + 2\text{O}_2 \rightarrow 2\text{CO}_2 + 3\text{H}_2$
C. $2\text{C}_2\text{H}_6 + 5\text{O}_2 \rightarrow 4\text{CO} + 6\text{H}_2\text{O}$
D. $2\text{C}_2\text{H}_6 + 7\text{O}_2 \rightarrow 4\text{CO}_2 + 6\text{H}_2\text{O}$