The passages of a current of electricity through acidulated water and solution of copper sulphate liberate 203 cc of hydrogen at S.T.P. and deposits 0.571 g of copper. Calculate the equivalent weight of copper. (Wt. of 1 cc of hydrogen is 0.00009 g).

Volume of hydrogen liberated at S.T.P = 203 cc
Wt. of 1 cc of hydrogen = 0.00009 g
Wt. of hydrogen liberated at S.T.P. = 203 × 0.00009 g = 0.01827 g
Wt. of copper deposited = 0.571 g
Eq. wt. of hydrogen = 1.008
We know, Wt. of copper/Wt.of hydrogen=Eq.wt.of copper/Eq.wt.of hydrogen
$\Rightarrow \large\frac{0.571}{0.01827}=\frac{X}{1.008}$
$\Rightarrow X=31.49$
Therefore, the equivalent weight of copper is 31.49.
Hence (A) is the correct answer.