# The electrochemical equivalent of a metal is $3.3 \times 10^{−7}$ at the cathode when a $3\: A$ current is passed for 2 seconds will be kg per coulomb. The mass of the metal liberated

$\begin {array} {1 1} (A) 19.8 \times 10^{âˆ’7} kg \\ (B) 9.9 \times 10^{âˆ’7} kg \\ (C) 6.6 \times 10^{âˆ’7} kg \\ (D) 1.1 \times 10^{âˆ’7} kg \end {array}$

This question requires the student to have a basic understanding of electrochemical reactions
$M = Z \: i\: t$
$M = 3.3 \times 10^{−7} kg \times 3 \times 2 = 19.8 \times 10^{−7} kg$
Ans : (A)

edited Mar 14, 2014