Cambridge IGCSE Chemistry - 0620 - Supplement Paper 2 2011 Winter Zone 2

In which substance are the particles close together and slowly moving past each other?
A. air
B. ice
C. steam
D. water

The diagram shows the electronic structures of atoms P and Q.


P and Q combine to form a molecule.
What is the formula of this molecule?
A PQ₄ B PQ C P₂Q D P₄Q

A student was provided with only a thermometer, a stopwatch and a beaker.
What could the student measure?
A. 10.5 g solid and 24.8 cm³ liquid
B. 10.5 g solid and 25°C
C. 24.8 cm³ liquid and 45 seconds
D. 25°C and 45 seconds

Two isotopes of helium are $^3_2 ext{He}$ and $^4_2 ext{He}$.
Which two diagrams show the arrangement of particles in these two isotopes?
[Image_1: Diagrams with arrangements of particles for $^3_2 ext{He}$ and $^4_2 ext{He}$]
Key: ⊖ = electron, ⊕ = proton, ⊙ = neutron, ⊗ = nucleus.

Mixture 1 contains sand and water.
Mixture 2 contains salt and water.
Which method of separation could be used to obtain each of the required products from each mixture?

[Table_1]

+----------------+-----------------+-----------------+------------------+
| | mixture 1 | mixture 2 | |
| | to obtain sand | to obtain salt| to obtain water|
|----------------|-----------------|-----------------|------------------|
| A | crystallisation | distillation | filtration |
| B | crystallisation | filtration | filtration |
| C | filtration | filtration | crystallisation |
| D | filtration | distillation | crystallisation|
+----------------+-----------------+-----------------+------------------+

The relative formula mass, $M_r$, of copper(II) sulfate, $\text{CuSO}_4$, is 160.
Which mass of sulfur is present in 160g of copper(II) sulfate?
A 16g B 32g C 64g D 128g

Two elements, represented by ○ and ●, form a compound. Which diagram shows molecules of the compound?

The table describes the structures of four particles.

[Table_1]

What are the correct values of X, Y and Z?

[Table_2]

Metals could be extracted from their molten chlorides using electrolysis.
Which substances are formed at each electrode?
[Table_1]

The diagram shows a section of an overhead power cable.

Which statement explains why a particular substance is used?
A Aluminium has a low density and is a good conductor of electricity.
B Porcelain is a good conductor of electricity.
C Steel can rust in damp air.
D Steel is more dense than aluminium.

Concentrated aqueous potassium bromide solution is electrolysed using inert electrodes.
The ions present in the solution are $\text{K}^+$, $\text{Br}^-$, $\text{H}^+$ and $\text{OH}^-$.
To which electrodes are the ions attracted during this electrolysis?
[Table_1]

The sign ⇌ is used in some equations to show that a reaction is reversible. Two incomplete equations are given.

[Table_1]
reactants | products
P | CoCl₂ + 2H₂O → CoCl₂·2H₂O
Q | C + O₂ → CO₂

For which of these reactions can a ⇌ sign be correctly used to complete the equation?
[Table_2]
P | Q
A | ✓ | ✓
B | ✓ | ✗
C | ✗ | ✓
D | ✗ | ✗

Which fuel needs oxygen in order to produce heat energy and which type of reaction produces the energy?

[Table_1]

fuel | type of reaction
--------------------------
A. a radioactive isotope | endothermic
B. a radioactive isotope | exothermic
C. hydrogen | endothermic
D. hydrogen | exothermic

Some reactions are listed.

methane + oxygen → carbon dioxide + water
sodium + water → sodium hydroxide + hydrogen
magnesium + hydrochloric acid → magnesium chloride + hydrogen

Which word correctly describes all of these reactions?

A. combustion
B. endothermic
C. exothermic
D. neutralisation

Which type of reaction always forms a salt and water?
A. exothermic
B. neutralisation
C. oxidation
D. polymerisation

An experiment to determine the rate of a chemical reaction could be carried out using the apparatus shown.
Which reaction is being studied?
A. $Cl_2 + 2KBr \rightarrow 2KCl + Br_2$
B. $Mg + H_2SO_4 \rightarrow MgSO_4 + H_2$
C. $NaCl + AgNO_3 \rightarrow NaNO_3 + AgCl$
D. $NaOH + HCl \rightarrow NaCl + H_2O$

Copper(II) carbonate reacts with dilute sulfuric acid.
$$\text{CuCO}_3(\text{s}) + \text{H}_2\text{SO}_4(\text{aq}) \rightarrow \text{CuSO}_4(\text{aq}) + \text{CO}_2(\text{g}) + \text{H}_2\text{O}(\text{l})$$
The speed of the reaction can be changed by varying the conditions.
Which conditions would always increase the speed of this chemical reaction?
1 Increase the concentration of the reactants.
2 Increase the size of the pieces of copper(II) carbonate.
3 Increase the temperature.
4 Increase the volume of sulfuric acid.
A 1, 3 and 4
B 1 and 3 only
C 2 and 3
D 3 and 4 only

The table shows some properties of two elements in Group VII of the Periodic Table.

| element | state at 20°C | density / g per cm³ | melting point / °C |
|---------|---------------|----------------------|-------------------|
| chlorine| gas | 0.0032 | −101 |
| bromine | liquid | 3.1 | −7 |

Which properties is fluorine likely to have?

| | state at 20°C | density / g per cm³ | melting point / °C |
|----------|---------------|----------------------|-------------------|
| A | gas | 0.0017 | −220 |
| B | gas | 0.17 | −188 |
| C | liquid | 0.0017 | −220 |
| D | liquid | 0.17 | −188 |

Statement 1: Helium is a reactive gas.
Statement 2: Helium can be used to fill balloons.
Which is correct?
A Both statements are correct and statement 2 explains statement 1.
B Both statements are correct but statement 2 does not explain statement 1.
C Statement 1 is correct but statement 2 is incorrect.
D Statement 2 is correct but statement 1 is incorrect.

An alloy contains copper and zinc.
Some of the zinc has become oxidised to zinc oxide.
What is the result of adding an excess of dilute sulfuric acid to the alloy?
A. A blue solution and a white solid remains.
B. A colourless solution and a pink/brown solid remains.
C. The alloy dissolves completely to give a blue solution.
D. The alloy dissolves completely to give a colourless solution.

An element has the following properties.
• It forms coloured compounds.
• It acts as a catalyst.
• It melts at 1539°C.
In which part of the Periodic Table is the element found?
A Group I
B Group IV
C Group VII
D transition elements

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

[Table_1]

| test | result |
|----------------------------------|---------------------------------------------|
| aqueous sodium hydroxide added | white precipitate formed, soluble in excess |
| aqueous ammonia added | white precipitate formed, soluble in excess |
| dilute hydrochloric acid added | bubbles of gas |

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

Which property is not characteristic of a base?
A It reacts with a carbonate to form carbon dioxide.
B It reacts with an acid to form a salt.
C It reacts with an ammonium salt to form ammonia.
D It turns universal indicator paper blue.

A liquid turns white anhydrous copper sulfate blue and has a boiling point of 103°C.
Which could be the identity of the liquid?
A. alcohol
B. petrol
C. salt solution
D. pure water

Alloy X is strong and has a low density.
Alloy Y is heavy but is resistant to corrosion.
Which could be uses of X and Y?

[Table_1]

Which statements are correct?
1 Metals are often used in the form of alloys.
2 Stainless steel is an alloy of iron.
3 Alloys always contain more than two metals.
A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

Which statement is true about all metals?
A. They are attracted to a magnet.
B. They are weak and brittle.
C. They may be used to form alloys.
D. They react with water.

A metal is extracted from hematite, its oxide ore.
What is the metal and how is the oxide reduced?
[Table_1]

A chemical engineer plans to produce hydrochloric acid.
Which metal is best for the reaction container?
A copper
B iron
C magnesium
D zinc

When sodium reacts with water, a solution and a gas are produced. [Image_1: diagram of sodium on water]

The solution is tested with litmus paper and the gas is tested with a splint.

What happens to the litmus paper and to the splint?

[Table_1]
| | litmus paper | splint |
|--------|--------------|--------------------------|
| A | blue to red | glowing splint relights |
| B | blue to red | lighted splint ‘pops’ |
| C | red to blue | glowing splint relights |
| D | red to blue | lighted splint ‘pops’ |

Iron is a metal that rusts in the presence of oxygen and water.
Mild steel is used for ……1…… and is prevented from rusting by ……2…… .
Stainless steel is prevented from rusting by ……3…… it with another metal.
Which words correctly complete gaps 1, 2 and 3?

| | 1 | 2 | 3 |
|---|-----------|-----------|---------|
| A | car bodies | greasing | covering |
| B | car bodies | painting | mixing |
| C | cutlery | greasing | covering |
| D | cutlery | painting | mixing |

Dry air is passed over hot copper until all the oxygen has reacted.

The volume of gas at the end of the reaction is 120 cm³.
What is the starting volume of dry air?

A) 132 cm³
B) 150 cm³
C) 180 cm³
D) 600 cm³

In which row is the air pollutant not correctly matched with its source?
[Table_1]

[Table_1]:

Which pollutant gas is produced by the decomposition of vegetation?
A carbon monoxide
B methane
C nitrogen oxide
D sulfur dioxide

Which combination of chemical compounds could be used to produce the fertiliser shown?

A. NH₄NO₃, Ca₃(PO₄)₂
B. NH₄NO₃, CO(NH₂)₂
C. NH₄NO₃, K₂SO₄, (NH₄)₂SO₄
D. (NH₄)₃PO₄, KCl

The diagram represents the molecule of an organic compound.

What is the name of the compound?
A. ethane
B. ethanoic acid
C. ethanol
D. ethene

When glucose is fermented, ethanol is formed together with
A. carbon dioxide.
B. ethene.
C. methane.
D. oxygen.

The table shows the composition of four different types of petroleum (crude oil).

[Table_1]

Which type of petroleum is best for the motor vehicle industry?
A Arabian Heavy
B Arabian Light
C Iranian Heavy
D North Sea

Which pair of compounds are members of the same homologous series?
A:
[Image_A1] [Image_A2]
B:
[Image_B1] [Image_B2]
C:
[Image_C1] [Image_C2]
D:
[Image_D1] [Image_D2]

Petroleum is a very important raw material that is separated into more useful products.
Which terms describe petroleum and the method used to separate it?
[Table_1: petroleum is a -> method used to separate petroleum
A compound -> cracking
B compound -> fractional distillation
C mixture -> cracking
D mixture -> fractional distillation]