Assertion : Atoms can neither be created nor destroyed. Reason :...

Atoms can neither be created nor destroyed. This is the statement of law of conservation of mass. Under similar conditions of temperature and pressure, equal volume of gases contain equal number of atoms. As, $P V=n R T$ (Ideal gas equation) If, for Ist case, for IInd case, $$\begin{aligned}& P_1 V_1=n_1 R T_1 \\ & P_2 V_2=n_2 R T_2 \end{aligned}$$\Rightarrow \quad $\frac{P_1 V_1}{P_2 V_2}=\frac{n_1 R T_1}{n_2 R T_2} \Rightarrown_1=n_2\left(\becauseP_1,=P_2, V_1=V_2, T_1=T_2\right)