Question

Nitrogen cannot be obtained by heating :

• A. $Pb\left(N_3{)}_2\right(s)$
• B. $KN{O}_3\left(s\right)$
• C. $\left(N{H}_4{)}_{2}C{r}_2{O}_7\right(s)$
• D. $N{H}_{4}N{O}_2\left(s\right)$

Answer 1

The correct option is B $KN{O}_3\left(s\right)$

$2Pb\left(N_3{)}_2\right(s)\stackrel{△}{\to }2Pb+3N_2$

$KN{O}_3\to KN{O}_2+\frac{1}{2}{O}_2$

$\left(N{H}_4{)}_{2}C{r}_2{O}_7\right(s)\stackrel{\Delta }{\to }{N}_2+4H_{2}O+C{r}_2{O}_3$

$N{H}_{4}N{O}_2\left(s\right)\stackrel{\Delta }{\to }{N}_2+2H_{2}O$

So, nitrogen cannot be obtained by heating $KN{O}_3$.

Hence option B is correct.