A piece of metal weighing 200 g is to be electroplated with 5% of its weight in gold. How long it would take to deposits the required amount of gold, if the strength of the available current is 2 A? (Given, electrochemical equivalent of $H = 0.0104 imes 10^{- 4}\ gC^{- 1}\ $atomic weight of gold = 197.1, atomic weight of hydrogen = 1.008)

Question

A piece of metal weighing 200 g is to be electroplated with 5% of its weight in gold. How long it would take to deposits the required amount of gold, if the strength of the available current is 2 A? (Given, electrochemical equivalent of $H = 0.0104 	imes 10^{- 4}\ gC^{- 1}\ $atomic weight of gold = 197.1, atomic weight of hydrogen = 1.008)

Dr. Abubacker · Accepted Answer

(a) Chemical equivalent of gold $= \frac{197.1}{3} = 65.7$
Gold to be deposited $= \frac{200 	imes 5}{100} =$10g
Electrochemical equivalent of gold
${\ \ \ \ z}_{2} = \frac{W_{2}}{W_{1}}z_{1}\ z_{2} = \frac{65.7}{1.008} 	imes 0.1044 	imes 10^{- 4}gC^{- 1}$
Also$\ m = zlt,\ t = \frac{m}{zl}$
$\Rightarrow \  = \frac{10}{\left( \ \frac{65.7}{1.008} 	imes 0.1044 	imes 10^{- 4} 	imes 2 ight)}$
= 7347.9s

Explanation

Reviewed by Dr. Abubacker

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