JUNE 2020

A student needs to measure 17.60 cm³ of hydrochloric acid. The student has access to the

apparatus commonly found in a school laboratory.

Which piece of equipment should be used to measure the 17.60 cm³ of hydrochloric acid?

• a burette

• a gas syringe

• a measuring cylinder

• a pipette

When calcium carbonate is added to dilute hydrochloric acid, carbon dioxide gas is released.

Three sets of apparatus are shown.

Which sets of apparatus are suitable, together with a stop-watch, for following the rate of this

reaction?

• 1, 2 and 3

• 1 and 2 only

• 2 only

• 2 and 3 only

Petroleum (crude oil) is separated into useful fractions by fractional distillation. The positions at

which fractions X and Y are collected from the fractionating column are shown.

Which statement is correct?

• The temperature increases up the column.

• X condenses at a lower temperature than Y.

• X has a higher boiling point than Y.

• X has longer chain molecules than Y.

Compound X is a crystalline solid at room temperature and pressure. An aqueous solution of X is

tested as shown.

What could be the identity of X?

• ammonium carbonate

• sodium sulfate

• calcium nitrate

• zinc chloride

When aqueous sodium hydroxide is added to a solution, a white precipitate forms which dissolves when excess sodium hydroxide is added.

Which ion could be present in the solution?

• Al³⁺(aq)

• Ca²⁺ (aq)

• Cu²⁺(aq)

• Na⁺(aq)

Why does a balloon full of helium gas become smaller as the temperature changes from 30 ^oC to

10 ^oC?

• The gas condenses to a liquid and so takes up less space.

• The gas particles become smaller at lower temperatures.

• The gas particles diffuse through the balloon and escape.

• The gas particles move more slowly so reducing the pressure.

The diagram of an ion is shown.

What can be deduced about the number of protons in this ion?

• It has 9 protons

• It has 10 protons.

• It has 11 protons

• You cannot deduce the number of protons from this diagram.

Which material has the highest melting point?

• ammonia

• methane

• sodium chloride

• water

Which statement describes ionic bonds?

• a lattice of ions in a ‘sea of electrons’

• electrostatic attraction between oppositely charged ions

• the sharing of electrons between atoms to gain a noble gas configuration

• the transfer of electrons from atoms of a non-metal to the atoms of a metal

The diagram shows the covalent bonds in an organic compound.

The total number of electrons in one molecule of this compound is ......X...... .

The total number of electrons in the bonds in one molecule of this compound is ......Y...... .

Which numbers correctly complete gaps X and Y?

• X = 14, Y = 12

• X = 14, Y = 14

• X =18, Y = 12

• X = 18, Y = 14