Question

A current of $2.0\, A$ passed for $5$ hours through a molten metal salt deposits $22.2\, g$ of metal (At wt. = $177$). The oxidation state of the metal in the metal salt is

• A. + 1
• B. +2
• C. +3
• D. +4

Answer 1

Answer: (C)

Weight $=\frac{E \times i \times t}{F}=\frac{\text { M it }}{n-\text { factor } \times F} \mid E=\frac{M}{n-\text { factor }}$
$\Rightarrow 22.2=\frac{177 \times 5 \times 2 \times 60 \times 60}{ n -\text { factor } \times 96500}$
$\therefore n -$ factor $=2.97 \simeq 3$
Hence oxidation state of metal $=+3$