Electrolysis...

[sandi]

Both electrodes are platinum.
Aqueous solution containing 0.1 mol of Cu(NO₃)₂,o.5 mol of AgNO₃ and 0.05mol of Al(NO₃)₃

a)After electrolysis has continued for some time, hydrogen gas is observed to be produced at the cathode.
i) Write the half-equations for all of the reactions which occurs at the cathode prior to the production of hydrogen gas.

I thought that it would only be Ag⁺ +e--->Ag that would occur at the cathode, why does Cu²⁺ +2e--->Cu also occur?

[rebeccab26]

Both electrodes are platinum.
Aqueous solution containing 0.1 mol of Cu(NO₃)₂,o.5 mol of AgNO₃ and 0.05mol of Al(NO₃)₃

a)After electrolysis has continued for some time, hydrogen gas is observed to be produced at the cathode.
i) Write the half-equations for all of the reactions which occurs at the cathode prior to the production of hydrogen gas.

I thought that it would only be Ag⁺ +e--->Ag that would occur at the cathode, why does Cu²⁺ +2e--->Cu also occur?

where is this q from?
like a trial paper or textbook?

[daniel034]

Species present: Ag+ Cu2+ H2O Al3+

In that order they go from highest to lowest on the left hand side of the electrochemical series

Because Cu2+ is a stronger oxidant than water, but not as strong as Ag+, it will react after all the Ag+ has been reduced.