IGCSE Coordinated Chemistry Workout 25

What is limestone?

• calcium carbonate

• calcium chloride

• calcium hydroxide

• calcium oxide

Four molecules are shown.

Which structure represents ethanol?

• A

• B

• C

• D

The diagram represents the structure of a lithium atom.

Which particles are found in the centre of the atom?

• proton and electron

• proton and neutron

• proton and nucleus

• electron and neutron

Three minerals containing iron are listed.

What is the total number of different elements contained in all three minerals?

• 3

• 4

• 5

• 16

The diagram shows the electrolysis of a compound. When the switch is closed, the solution around electrode P turns orange because a halogen is formed. The positive electrode P is called the ……1……, and the halogen is ……2…… .

Which words complete gaps 1 and 2?

• 1 = anode; 2 = bromine

• 1 = anode; 2 = chlorine

• 1 = cathode; 2 = bromine

• 1 = cathode; 2 = chlorine

Which statement about chemical reactions is correct?

• Endothermic reactions result in a temperature decrease.

• Endothermic reactions result in a temperature increase.

• Exothermic reactions always produce a large temperature rise.

• Exothermic reactions always produce a small temperature rise.

In a manned spacecraft, carbon dioxide is removed from the air by reacting with potassium hydroxide.

Which type of reaction occurs?

• decomposition

• neutralisation

• precipitation

• redox

Which test and result show that a fertiliser contains nitrate ions?

• A

• B

• C

• D

The diagram shows part of the Periodic Table.

Which letter shows the position of a metal with a low melting point?

• A

• B

• C

• D

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

A green halogen gas is bubbled through a potassium halide solution. The potassium halide solution turns brown–black.

What is the halogen and what is the potassium halide solution?

• A

• B

• C

• D

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2