C6

Question 1

When hydroxide ions are discharged at the anode, what are the products?

Answer 1

Oxygen

Question 2

What is added to aluminium oxide to lower its melting point during electrolysis?

Answer 2

Molten cryolite

Question 3

Why do the carbon anodes used in aluminium extraction need to be replaced?

Answer 3

The oxygen reacts with the anodes to form carbon dioxide which gradually causes them to break down

Question 4

Write two half equations showing what happens to aluminium and oxide ions during electrolysis:

Answer 4

Al3+ + 3e- → Al
2O2-→ O2 + 4e-

Question 5

What does electrolysis mean?

Answer 5

Breaking down [a substance] using electricity

Question 6

What process occurs at the cathode?

Answer 6

Reduction

Question 7

In aqueous solutions, the _____ reactive cation is discharged at the cathode

Answer 7

Less

Question 8

If a halide ion is present in an aqueous solution, will it be discharged at the anode during electrolysis?

Answer 8

Yes

Question 9

What is aluminium used for?

Answer 9

-power cables
-aeroplanes
-cooking foil
-bicycle frames