Question

Which salt on heating does not give brown coloured gas ?

• A. LiNO3
• B. KNO3
• C. Pb(NO3)2
• D. AgNO3

Answer 1

Answer: (B)

KNO3

Answer 2

(1) 2LiNO3 $\overset{\quad\Delta\quad}{\rightarrow}$ Li2O + 2NO2$\uparrow$ (brown) +$\frac{1}{2}$O2$\uparrow$

(2) KNO3$\overset{\quad\Delta\quad}{\rightarrow}$KNO2 +$\frac{1}{2}$O2$\uparrow$

(3) Pb(NO3)2 $\overset{\quad\Delta\quad}{\rightarrow}$PbO + 2NO2$\uparrow$ (brown) +$\frac{1}{2}$O2$\uparrow$

(4) 2AgNO3$\overset{\quad\Delta\quad}{\rightarrow}$2Ag + 2NO2$\uparrow$ (brown) + O2$\uparrow$