Chemistry 0620 · IGCSE · Electrolysis

Electrolysis — practice question

This question concerns electricity and chemical reactions.
(a(i))[2]

State what the term electrolysis means.

(a(ii))[1]

State why graphite is a suitable material for an electrode.

(a(iii))[2]

Write an ionic half-equation for hydrogen formation at the cathode.

(a(iv))[1]

Name the kind of particle that transfers charge in conducting wires.

(a(v))[1]

Name the kind of particle that transfers charge in aqueous potassium bromide.

(a(vi))[2]

State the names of the products that are formed when electricity is passed through dilute aqueous potassium bromide using graphite electrodes at the anode and at the cathode.

(b(i))[1]

Name the aluminium compound found in purified bauxite.

(b(ii))[2]

State two reasons why cryolite is used in this electrolysis.

(b(iii))[1]

Explain why the carbon anode must be replaced regularly.

(c(i))[2]

Write the symbol equation for the overall reaction in a hydrogen-oxygen fuel cell.

(c(ii))[1]

State one advantage of using hydrogen-oxygen fuel cells instead of petrol in vehicle engines.

Worked solution & mark scheme

This 16-mark question has a full step-by-step worked solution and mark scheme. One marking point: Decomposition by passage of electricity

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI