The weight of hydrogen deposited at cathode when 965 amperes current is passed for 100 seconds through acidulated water is

When acidualted water is electrolysed, the cathodic reactionis 

$2H^{+}+ 2e^{-}\to H_2$

n=2 electrons 

According to Faraday's law, 

$w=\frac{M\times i\times t}{n\times 96500}$

w= mass of substance deposited (g)

M= molecular mass (g/mol) 

i = current (amp) 

t= time (sec) 

$w=\frac{2 \times 965\times 100}{2\times 96500}$

w= 1 g .