The electrolysis of aqueous solutions
1 mark · EasyState why the volume of chlorine gas collected at the anode is usually less than expected during the electrolysis of concentrated sodium chloride solution.
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Chlorine gas is more soluble in water than hydrogen, so less is collected.
Also accept: Some chlorine dissolves in the water.; Chlorine gas dissolves in water.
Common mistakes: Chlorine reacts with water.; Gas escapes.
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Marking points
B1 · 1 mark · States that chlorine gas is more soluble in water (or that it dissolves in water), so less is collected.
Worked solution
Chlorine gas is more soluble in water than hydrogen, so some of it dissolves in the solution and less is collected at the anode.