Electrolysis of Lead Bromide

Question 1

[ ] Lead bromide can be broken down by electrolysis. You end up with [ ] and [ ]

Answer 1

Molten

Lead and Bromine

Question 2

[ ] ions are attracted to the negative electrode. Here they [ ] electrons ([ ])

Answer 2

Positive

gain (reduction)

Question 3

[ ] ions are attracted to the positive electrode. Here they [ ] electrons ([ ])

Answer 3

Negative

lose (oxidation)

Question 4

What is produced at the negative electrode?

Answer 4

Lead

Question 5

What is produced at the positive electrode?

Answer 5

Bromine

Question 6

What happens at the negative electrode?

Answer 6

One lead ion accepts 2 electrons to become 1 lead atoms

Question 7

What happens at the positive electrode?

Answer 7

2 bromide ions LOSE 1 electron each and become 1 bromine molecule

Question 8

[ ] affects the products formed by electrolysis

Answer 8

Reactivity

Question 9

Sometimes there are more than 2 free ions in the electrolyte. Give and example

Answer 9

If a slat is dissolved in water there will also be some H+ and OH- ions

Question 10

What happens at the -ve electrode if there are more than 2 free ions in the electrolyte?

Answer 10

If metal ions and H+ ions are present, the metal ions will stay in solution if the metal is MORE reactive than hydrogen.
This is because the more reactive an element, the keener it is to stay as ions. So, hydrogen will be produced UNLESS the metal is less reactive than it

Question 11

What happens at the +ve electrode if there are more than 2 free ions in the electrolyte?

Answer 11

If OH- and halide ions (Cl-, Br-, I-) are present then molecules of chlorine,, bromine or iodine will be formed. If no halide is present, then oxygen will be formed