Question

$12g$ of alkaline earth metal givess $14.8g$ of its nitrite atomic weight of metal is:

• A. $12$
• B. $20$
• C. $40$
• D. $14.8$

Answer 1

The correct option is C $40$

$3M+N_2⟶M_3{N}_2\left[Nitride\right]$
$3x$ $3x+28$
So, $\frac{12}{3x}=\frac{14.8}{3x+28}$
Solving for $x$ gives $x=40$
So, the element is calcium with atomic weight $=40$.