Q33 / 155 · WBJEE 2018 · Chemistry
A metal $M$ (specific heat 0.16 ) forms a metal chloride with $65 \%$ chlorine present in it. The formula of the metal chloride will be
- AMCI
- Correct answerB$M C l_{2}$
- C$M \mathrm{Cl}_{3}$
- D$M C l_{4}$
Solution
Given, specific heat $=0.16$
Let metal chloride be $M \mathrm{Cl}_{x}$ then. $\frac{6.4}{\text { specific heat }}=$ Atomic weight of metal $\frac{6.4}{0.16}=$ Atomic weight of metal
Atomic weight $=40$
40 is the atomic weight of calcium. According to question, metal chloride $\left(M C l_{x}\right)$ have $\approx 65 \%$ chlorine present in it. $\frac{x \times \text { Atomic weight of chlorine }}{40+x \times \text { Atomic weight of chlorine }} \times 100=65$
$$
\begin{array}{l}
\frac{x \times 355}{40+x \times 355} \times 100=65 \\
x=209 \approx 2(a p p r o x .)
\end{array}
$$
So, the formula of metal chloride will be $M \mathrm{Cl}_{2}$
Hence, the correct answer is option: 'B'.