Question

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
(A) \(\mathrm{MCl}\)
(B) \(\mathrm{MCl}_{2}\)
(C) \(\mathrm{MCl}_{3}\)
(D) \(\mathrm{MCl}_{4}\)

Answer 1

Ans: (B)
 Using Dulong Petit's law
At mass \((\) approx \() \times\) sp. heat \(=6.4\)
\(\therefore\) At. mass(approx) \(=\frac{6.4}{0.16}=40\)
Let formula is \(\mathrm{MCl}_{\mathrm{x}}\)
\(\therefore \%\) bymass of \(C l=\frac{x \times 35.5}{40+35.5 x} \times 100=65\)
\(\therefore \mathrm{x}=2.09 \simeq 2 \quad\) Hence it is \(\mathrm{MCl}_{2}\)