Question

Which of the following give no residue on heating ?

• A. $N{H}_{4}N{O}_3$
• B. $N{H}_{4}N{O}_2$
• C. $(N{H}_4{)}_{2}C{r}_2{O}_7$
• D. $N{H}_{4}Cl$

Answer 1

Answer: (A), (B), (D)

The correct options are
A $N{H}_{4}N{O}_3$
B $N{H}_{4}N{O}_2$
D $N{H}_{4}Cl$

$N{H}_{4}N{O}_3\left(g\right)\stackrel{\Delta }{\to }{N}_{2}O\left(g\right)+2H_{2}O\left(g\right)N{H}_{4}N{O}_2\left(s\right)\stackrel{\Delta }{\to }{N}_2\left(g\right)+2H_{2}O\left(g\right)\left(N{H}_4{)}_{2}C{r}_2{O}_7\right(s\left)\stackrel{\Delta }{\to }{N}_2\right(g)+C{r}_2{O}_3(s)+4H_{2}O(g\left)N{H}_{4}Cl\right(s\left)\stackrel{\Delta }{\to }N{H}_3\right(g)+HCl(g)$
Only on heating $(N{H}_4{)}_{2}C{r}_2{O}_7$, we get residue.