Question

A current of $9.65$ ampere flowing for $10$ minutes deposits $3.0g$ of the metal which is monovalent. The atomic mass of the metal is

• A. 10
• B. 50
• C. 30
• D. 96.5

Answer 1

Answer: (B)

$Q=It$
$=9.65\times 10\times 60$
$=5790C$
$\underset{\text{monovalent metal}}{M^{+}}+\underset{1F,96500C}{e}\to \underset{1mole}{M}$
With $5790C$, amount of metal deposited $=3gm$
With $96500C$, amount of metal deposited
$=\frac{3}{5790}\times 96500$
$=50g$(equivalent weight)
Atomic mass $=50\times$ valency
$=50\times 1=50$ amu