5 0 2
This question is about salts and electrolysis.
Do not write
outside the
box
A student wants to make copper chloride crystals.
The student adds excess copper oxide to some hot acid.
The student stirs the mixture.
0 2 . 1
Which acid should the student use?
[1 mark]
Tick (✓) one box
Hydrochloric acid
Nitric acid
Sulfuric acid

Consider the reduction reactions and their equilibrium constants. cu+(aq)+e−↽−−⇀cu(s)pb2+(aq)+2e−↽−−⇀pb(s)fe3+(aq)+3e−↽−−⇀fe(=6.2×108=4.0×10−5=9.3×10−3 cu + ( aq ) + e − ↽ − − ⇀ cu ( s ) k =6.2× 10 8 pb 2 + ( aq ) +2 e − ↽ − − ⇀ pb ( s ) k =4.0× 10 − 5 fe 3 + ( aq ) +3 e − ↽ − − ⇀ fe ( s ) k =9.3× 10 − 3 arrange these ions from strongest to weakest oxidizing agent.