IGCSE Aluminium Extraction / Uses of Metals

In the extraction of aluminium, what compound of aluminium is used for the electrolyte?

• aluminium oxide

• aluminium sulfate

• aluminium nitrate

• aluminium sulfide

To which electrode do aluminium ions move during the electrolysis?

• anode

• cathode

In aluminium extraction, the melting point of the electrolyte is lowered by adding (a)  

Which statements about the manufacture of aluminium by electrolysis is correct? Select all the correct options.

• Aluminium is extracted from its ore haematite.

• Aluminium ions gain electrons to form aluminium.

• The carbon anodes need to be replaced.

• Carbon dioxide is formed in the process.

• Limestone is added to remove impurities.

What substances must be present for rusting to occur?

Select all correct options.

• Heat

• Enzyme

• Oxygen

• Water

• UV light

Which metals can provide sacrificial protection against rusting? Select all correct options.

• iron

• steel

• zinc

• magnesium

• copper

Iron from the blast furnace is impure. To remove these impurities, .....

• add additives to molten iron.

• filter the molten iron.

• blow oxygen into molten iron.

• add coke to molten iron.

The malleability of iron ....... as the percentage of carbon in the iron increases.

• increases

• decreases

Stainless steel is made by adding additives such as .........

Select all correct options.

• chromium

• copper

• molybdenum

• titanium

• nickel

Which is NOT a use of zinc?

• Galvanizing

• Sacrificial protection

• Making brass

• Making bronze