Cambridge IGCSE Chemistry - 0620 - Supplement Paper 2 2009 Winter Zone 1

Aqueous lead(II) nitrate and aqueous potassium iodide are added to a dish containing water, as shown in the image below.
A yellow precipitate forms after a few minutes.
Which process occurs before the precipitate forms?
A diffusion
B distillation
C fermentation
D filtration

A student carries out an experiment to prepare pure magnesium sulfate crystals.
The diagram shows the first stage of the preparation.



He adds magnesium carbonate until no more reacts.
Which process should he use for the next stage?
A crystallisation
B evaporation
C filtration
D neutralisation

A student separates salt from a mixture of salt and sand.
What is the correct order of steps for the student to take?
A filter → evaporate → shake with water
B filter → shake with water → evaporate
C shake with water → evaporate → filter
D shake with water → filter → evaporate

Atom X has 8 more electrons than atom Y.
Student 1 says they are in the same group.
Student 2 says they are unreactive.
Which students can be correct?

[Table with student analysis:
student 1 | student 2
A ✓ | ✓
B ✓ | ✗
C ✗ | ✓
D ✗ | ✗ ]

Which number is different for isotopes of the same element?
A. number of electrons
B. number of full shells
C. number of nucleons
D. number of protons

Which atom has two more electrons than an atom of a noble gas?
A. aluminium
B. bromine
C. calcium
D. rubidium

Statements 1, 2 and 3 are about diamond and graphite.
1. They are different solid forms of the same element.
2. They each conduct electricity.
3. They have atoms that form four equally strong bonds.
Which statements are correct?
A. 1 only B. 3 only C. 1 and 3 D. 2 and 3

Covalent bonds are formed when electrons are ......1...... . Covalent compounds have ......2...... electrical conductivity.
Which words correctly complete gaps 1 and 2?

[Table_1]

Which change to an atom occurs when it forms a positive ion?

A. It gains electrons.
B. It gains protons.
C. It loses electrons.
D. It loses protons.

For each atom of carbon present in a molecule, there is an equal number of atoms of oxygen but twice as many atoms of hydrogen.
What is the formula of the molecule?
A $ \text{C}_2\text{H}_2\text{O}_2 $ B $ \text{C}_2\text{H}_2\text{O}_4 $ C $ \text{C}_2\text{H}_4\text{O}_2 $ D $ \text{C}_2\text{H}_6\text{O} $

Water is formed when 48 g of oxygen combine with 6 g of hydrogen.
What mass of oxygen combines with 2 g of hydrogen?
A 12 g
B 16 g
C 96 g
D 144 g

The diagram shows how aluminium is manufactured by electrolysis.
What are the anode and cathode made of?
[Table_1]

The diagram shows the electrolysis of concentrated aqueous sodium chloride.

What is the colour of the Universal Indicator at each electrode after five minutes?
[Table_1]

The diagram shows an electrical cable.

Which statement about the substances used is correct?
A The coating is plastic because it conducts electricity well.
B The core is copper because it conducts electricity well.
C The core is copper because it is cheap and strong.
D The core is iron because it is cheap and strong.

Substance X requires oxygen in order to produce energy.

It does not form carbon dioxide as a result of this energy production.

What is substance X?

A. hydrogen
B. natural gas
C. petrol
D. $^{235}\text{U}$

When an acid is added to an alkali the temperature rises.
Which words describe this reaction?
A decomposition and endothermic
B decomposition and exothermic
C neutralisation and endothermic
D neutralisation and exothermic

When blue copper(II) sulfate is heated, a white solid and water are formed.
The white solid turns blue and gives out heat when water is added to it.
Which terms describe the blue copper(II) sulfate and the reactions?

[Table_1]

The equations represent redox reactions.
In which equation is the underlined substance acting as a reducing agent?
A \underline{\text{CaO}} + \text{H}_2\text{O} \rightarrow \text{Ca(OH)}_2
B \underline{\text{CO}_2} + \text{C} \rightarrow 2\text{CO}
C \underline{\text{CuO}} + \text{H}_2 \rightarrow \text{Cu} + \text{H}_2\text{O}
D \underline{3\text{CO}} + \text{Fe}_2\text{O}_3 \rightarrow 2\text{Fe} + 3\text{CO}_2

Which change does not increase the speed of reaction between zinc and hydrochloric acid?
A. adding a catalyst
B. decreasing the temperature
C. decreasing the particle size of the zinc
D. using more concentrated acid

An aqueous solution Y contains both barium ions and silver ions. In separate experiments, dilute sulfuric acid and dilute hydrochloric acid are added to solution Y. Which of these acids causes a precipitate to form in solution Y?
[Table_1]

The diagram shows the pH values of four solutions.

Which of these solutions are alkaline?
A P only
B P and Q only
C Q, R and S only
D R and S only

The diagram shows the position of an element X in the Periodic Table.

What is the correct classification of element X and its oxide?

Salts can be prepared by reacting a dilute acid
1. with a metal;
2. with a base;
3. with a carbonate.
Which methods could be used to prepare copper(II) chloride?
A. 1 and 2 only
B. 1 and 3 only
C. 2 and 3 only
D. 1, 2 and 3

Astatine is an element in Group VII of the Periodic Table. It has only ever been produced in very small amounts. What is the best description of its likely properties?

[Table_1]

Elements in Group 0 of the Periodic Table have uses.
These noble gases are ......1...... and this explains why argon ......2...... be used in lamps.
Which words correctly complete gaps 1 and 2?
[Table_1]

The table gives information about four elements.

[Table_1]

Which element is a transition metal?

Which statement about alloys is not correct?
A. Alloys are more expensive than the metals they are made from.
B. Alloys are mixtures of different metals.
C. Alloys are not as strong as the metals they are made from.
D. Alloys conduct electricity well.

Compound X is heated with carbon using the apparatus shown.
A brown solid is formed in the reaction tube and the limewater turns cloudy.
What is compound X?
A) calcium oxide
B) copper(II) oxide
C) magnesium oxide
D) sodium oxide

Some reactions of three metals are listed in the table.

[Table_1]

What is the order of reactivity of the metals?

[Table_2]

Which property do all metals have?
A They are soluble in water.
B They conduct electricity.
C They have high melting points.
D They react with dilute sulfuric acid.

Which object is \textit{least} likely to contain aluminium?
A. a bicycle frame
B. a hammer
C. a saucepan
D. an aeroplane body

A newspaper article claims that carbon dioxide is formed as follows.
1. during respiration
2. when calcium carbonate reacts with hydrochloric acid
3. when methane burns in air
Which statements are correct?
A. 1, 2 and 3
B. 1 and 2 only
C. 1 and 3 only
D. 2 and 3 only

Which iron nail rusts?
[Image_1: Four nails in test tubes labeled A (zinc coated nail), B (painted nail), C (nail in damp cloth), D (nail covered in grease)]

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

[Image_1: A diagram showing a planet and its atmosphere is labeled]

The table shows the composition of the atmosphere.

[Table_1]
| gas | percentage by volume |
|------------------|----------------------|
| carbon dioxide | 4 |
| nitrogen | 72 |
| oxygen | 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

Water must be purified before it is suitable for use in the home.
Which processes are used to remove solid impurities and bacteria?
[Table_1: Table showing columns for 'to remove solid impurities' and 'to remove bacteria'.
Options A, B, C, D with respective processes as follows:
'A: chlorination, chlorination',
'B: chlorination, filtration',
'C: filtration, chlorination',
'D: filtration, filtration']

Fertilisers are used to provide three of the elements needed for plant growth. Which two compounds would give a fertiliser containing all three of these elements?
A) Ca(NO₃)₂ and (NH₄)₂SO₄
B) Ca(NO₃)₂ and (NH₄)₃PO₄
C) KNO₃ and (NH₄)₂SO₄
D) KNO₃ and (NH₄)₃PO₄

The apparatus shows an experiment used to test gas X.

The bromine solution quickly becomes colourless.
What is the structure of gas X?
A H−C−H
B H
|
H−C═C−H
|
H
C H H
| |
H−C−C−H
| |
H H
D H H H H
| | | |
H−C−C−C−C−H
| | | |
H H H H

Which statement about petroleum is not correct?
A. It can be separated into useful substances by fractional distillation.
B. It consists mainly of hydrocarbons.
C. It is found underground in many parts of the world.
D. Its main use is for making lubricants and polishes.

Butene and hexene belong to the same homologous series. What is the same for butene and hexene?
A boiling point
B functional group
C number of hydrogen atoms per molecule
D relative molecular mass

The table shows the formulae of members of the alkane series.
[Table_1]

[Table_1]:
| name of compound | formula |
|------------------|---------|
| methane | CH₄ |
| ethane | C₂H₆ |
| propane | ? |
| butane | C₄H₁₀ |
| pentane | C₅H₁₂ |

What is the formula of propane?
A C₂H₈
B C₃H₇
C C₃H₈
D C₃H₉