Assertion (A) The reaction
$$\begin{aligned} 2 \mathrm{NO}+\mathrm{O}_2 & \longrightarrow 2 \mathrm{NO}_2 \\ \text { and } \quad 2 \mathrm{CO}+\mathrm{O}_2 & \longrightarrow 2 \mathrm{CO}_2 \end{aligned}$$
proceeds at the same rate because they are similar.
Reason (R) Both the reactions have same activation energy.
Assertion (A) The boiling points of alkyl halides decrease in the order $$R \mathrm{I}>R \mathrm{Br}>\mathrm{RCl}>\mathrm{RF}$$.
Reason (R) The boiling points of alkyl chlorides, bromides and iodides are considerably higher than that of the hydrocarbon of comparable molecular mass.
Assertion (A) $$\mathrm{N}_2$$ is less reactive than $$\mathrm{P}_4$$.
Reason (R) Nitrogen has more electron gain enthalpy than phosphorus.
Assertion (A) The molecular mass of the polymers cannot be calculated using the boiling point or freezing point method.
Reason (R) The freezing point method is used for determining the molecular mass of small molecules.