IGCSE: Exam-Style Questions#2

The equation for the reaction of zinc oxide with carbon monoxide is shown.

ZnO + CO → Zn + CO2

Which statement explains the role of carbon monoxide in this reaction?

• It is the oxidising agent and it is oxidised.
• It is the oxidising agent and it is reduced.
• It is the reducing agent and it is oxidised.
• It is the reducing agent and it is reduced.

Dilute hydrochloric acid is tested with universal indicator and with calcium carbonate.

Which row shows the pH and describes the reaction with calcium carbonate?

• A
• B
• C
• D

The results of two tests on a solution of substance R are shown.

What is R?

• iron(II) carbonate
• iron(III) carbonate
• iron(II) chloride
• iron(III) chloride

The character of the elements changes from metallic to non-metallic across a period of the Periodic Table.

Which statement explains this change?

• Metal atoms need to gain electrons to form metal ions.
• It becomes more difficult for elements to lose electrons across a period.
• Non-metal atoms lose electrons more easily than metal atoms.
• Atoms get bigger across a period.

Copper oxide and excess carbon are mixed together.

The mass before heating is 12.2 g.

The mixture is heated strongly and allowed to cool.

The mass after heating is 10.4 g.

Why does the mass change?

• Carbon forms carbon dioxide which then combines with the copper oxide.
• Carbon reduces the copper oxide and leaves the test-tube as carbon dioxide.
• Copper oxide loses oxygen, turns into copper and the carbon remains unchanged.
• Carbon oxidises the copper oxide and leaves the test-tube as carbon dioxide.

Which statement about both carbon dioxide and methane is correct?

• Increased concentrations of carbon dioxide and methane in the air cause an enhanced greenhouse effect.
• Methane and carbon dioxide are hydrocarbons.
• Respiration increases the concentration of carbon dioxide and methane in the air.
• The combustion of fossil fuels increases the concentration of carbon dioxide and methane in the air.

Why are alkanes members of the same homologous series?

• They are all hydrocarbons.
• They have similar physical properties.
• They have the same general formula.
• They all undergo combustion to give carbon dioxide and water

What are the products of cracking large alkane molecules?

• smaller alkanes only
• smaller alkenes only
• smaller alkanes, alkenes and hydrogen
• smaller alkanes and hydrogen only

The graph shows the motion of a cyclist over a period of 30s.

Which distance does the cyclist travel?

• 90m
• 105m
• 115m
• 120m

A solid cuboid block of metal has density ρ. The diagram shows its dimensions.

Which expression is used to calculate the mass of the block?

• ρ/xy

• ρ/xyz

• ρxy

• ρxyz