Question

The equivalent weight of a solid element is found to be $9$. If the specific heat of this element is $ 1.05\,J{{g}^{-1}}{{K}^{-1}}, $ then its atomic weight is:

• A. 17
• B. 21
• C. 25
• D. 27

Answer 1

Answer: (D)

By using :
Valency of an element
$=\frac{\text { Approximate weight }}{\text { Equivalent weight }} $
$=\frac{26.8 / \text { specific heat }}{\text { Equivalent weight }} $
$=\frac{26.8 / 1.05}{9}=2.835 \cong 3$
Now, by using
Atomic weight = Equivalent weight $\times$ valency
$= 9 \times 3 = 27$