Question

An organic compound made of $C$, $H$ and $N$ contains $20\%$ nitrogen. What will be its molecular mass if it contains only one nitrogen atom in it?

• A. $70$
• B. $140$
• C. $100$
• D. $65$

Answer 1

Answer: (A)

$70$

% nitrogen in compound $=\frac{14\times no.ofnitrogenatom}{molecularmass}\times 100$

20 = $\frac{14\times 1}{Molecularmass}\times 100$

Molecular mass = 70g