C3-6 Electrolysis

What does the word electrolysis mean?

• Spitting using electricity

• Extraction of metals

• Splitting with electricity

• Reduction at the cathode

In which state/s of matter does electrolysis take place?

• Solid

• Liquid

• Gas

• Aqueous

Which ions are attracted to the negative electrode in electrolysis?

• Anion

• Cation

• Anode

• Cathode

In the electrolysis of molten lead bromide, which equation shows the reaction at the cathode?

• Pb2+ + e- -> Pb

• Br- -> Br + e-

• Pb2+ + 2e- -> Pb

• 2Br- -> Br2 + 2e-

In the electrolysis of molten lead bromide, which equation shows the reaction at the anode?

• Pb2+ + e- -> Pb

• Br- -> Br + e-

• Pb2+ + 2e- -> Pb

• 2Br- -> Br2 + 2e-

Why can aluminium cannot be extracted from its ore by displacement with carbon in a blast furnace?

• Its too reactive and so is placed above carbon in the reactivity series

• The ore, bauxite, is too expensive for extraction in a blast furnace

• Only electrolysis purifies the bauxite ore readily for aluminium extraction

• Bauxite ore is aluminium oxide

Aluminium is extracted from its ore, bauxite which is aluminium oxide. The correct formula for aluminium oxide is...

• AlO

• Al2O3

• ALO3

• Al3O2

In the electrolysis of molten aluminium oxide, which equation shows the reaction at the cathode?

• Al2+ + 2e- -> Al

• Al2+- -> Al + 2e-

• Al3+ + 3e- -> Al

• Al3+- -> Al2 + e-

In the electrolysis of molten Aluminium oxide, which equation shows the reaction at the anode?

• O2+ + 2e- -> O2-

• O- -> O + e-

• O2- + 2e- -> O2

• 2O2- -> O2 + 4e-

Aluminium is extracted from its ore, bauxite, by electrolysis. Which is equation shows the overall change in this reaction

• Al2O3 -> Al + O

• Al2O3 -> Al + O2

• Al2O3 -> Al2 + O3

• 2Al2O3 -> 4Al + 3O2