Question

E.C.E. of a substance is its mass liberated at an electrode by what amount of current in half a second

• A. 4A
• B. 3A
• C. 2A
• D. 1A

Answer 1

The correct option is C 2A

E.C.E of a substance(Z) is the mass(m) of ions liberated by the passage of 1A current for one second through its electrolytic solution.
$Z=\frac{m}{It}$
$I=\frac{m}{Zt}$
If $t=\frac{1}{2}$
$I^{\prime }=\frac{m}{Z\frac{t}{2}}$
$I^{\prime }=2\frac{m}{Zt}$
$I^{\prime }=2I=2A$