AQA GCSE Chemistry: Electrolysis

Fill-in-the-blank revision flashcards covering the core concepts, rules, equations, and applications of electrolysis from AQA GCSE Chemistry.

Electrolysis is the decomposition of an ionic compound using __________.

electricity

For electrolysis to occur, the ionic compound must be __________ or aqueous.

molten

In electrolysis, the cathode has a __________ charge and the anode has a positive charge.

negative

In electrolysis, a cation is a __________ ion and an anion is a negative ion.

positive

At the cathode, positive ions gain electrons and are __________.

reduced

At the anode, negative ions lose electrons and are __________.

oxidised

The mnemonic OIL RIG stands for Oxidation Is Loss, Reduction Is __________.

Gain

In molten compounds, only ions from the __________ are present.

compound

During the electrolysis of molten lead bromide, the half-equation at the cathode is __________.

$$Pb^{2+} + 2e^- \rightarrow Pb$$

During the electrolysis of molten lead bromide, the half-equation at the anode is __________.

$$2Br^- \rightarrow Br_2 + 2e^-$$

Aqueous solutions contain ions from the compound as well as $H^+$ and __________ ions from water.

$$OH^-$$

According to the cathode rule for aqueous solutions, metals more reactive than hydrogen produce __________.

hydrogen

According to the cathode rule for aqueous solutions, metals less reactive than hydrogen are __________.

discharged

According to the anode rule for aqueous solutions, halides produce halogens; otherwise, __________ is produced.

oxygen

Electrolysis of brine produces hydrogen at the cathode and __________ at the anode.

chlorine

Electrolysis of copper sulfate produces __________ at the cathode and oxygen at the anode.

copper

Extraction of aluminium uses electrolysis because aluminium is more reactive than __________.

carbon

During the extraction of aluminium, __________ is added to lower the melting point.

Cryolite

__________ coats an object with a thin layer of metal.

Electroplating