Electroplating efficiency. 56Nickel was electrolytically plated onto a carbon electrode from a bath containing290g/LNiSO4.6H2O,30g/LB(OH)3androle="math" localid="1654763379590" 8g/LNaClat-1.2VvsAgAgClThe most important side reaction is reduction ofH+toH2.In one experiment, a carbon electrode weighing0.4775gbefore deposition weighedrole="math" localid="1654763622546" 0.4798gafter8.82Chad passed through the circuit. What percentage of the current went into the reactionNi2+2e-Ni(s)?

Short Answer

Expert verified

The percentage of the current that went into the reaction isw=93.57%

Step by step solution

01

Electroplating efficiency:

Current efficiency may be used to calculate the amount of metal deposited at the cathode or dissolved at the anode under conventional electroplating circumstances. Cathode efficiency is current efficiency applied to the cathode reaction, whereas anode efficiency is current efficiency applied to the anode reaction.

02

Calculate how much Ni is deposited:

First we need to calculate how much is deposited:

m(Ni)=(0.4798-0.4775)g=2.3.10-3g

Then we calculate of Ni:

n(Ni)=m(Ni)M(Ni)=2.3.10-3g58.69g/moln(Ni)=3.92.10-5mol

03

Find he percentage of the current that went into the reaction is:

Now we calculate charge of Ni:

q(NI)=n(Ni).F.Zq(Ni)=3.92.10-5mol.96485C/mol.2q(Ni)=7.562C

The percentage of the current that went into the reaction is:

w=7.562C8.082C.100%W=93.57%

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