At $345 \ K$,the half-life for the decomposition of a sample of a gaseous compound initially at $55.5 \ kPa$ was $340 \ s$. When the pressure was $27.8 \ kPa$,the half-life was found to be $170 \ s$. The order of the reaction is $......$ [integer answer]

For a chemical reaction $A \rightarrow B$,the rate of the reaction is $2 \times 10^{-3} \ mol \ dm^{-3} \ s^{-1}$,when the initial concentration is $0.05 \ mol \ dm^{-3}$. The rate of the same reaction is $1.6 \times 10^{-2} \ mol \ dm^{-3} \ s^{-1}$ when the initial concentration is $0.1 \ mol \ dm^{-3}$. The order of the reaction is

The rate law for the reaction,$NO_{2(g)} + CO_{(g)} \rightarrow NO_{(g)} + CO_{2(g)}$ is given as $R = k[NO_2]^2$. What is the order of reaction with respect to $CO$?

Units of rate constant of first and zero order reactions in terms of molarity $M$ unit are respectively

Define the following terms:
$(1)$ Elementary reaction
$(2)$ Complex reaction

Mechanism of a hypothetical reaction $X_2 + Y_2 \rightarrow 2XY$ is given below:
$(i)$ $X_2 \rightarrow X + X$ (fast)
$(ii)$ $X + Y_2 \rightleftharpoons XY + Y$ (slow)
$(iii)$ $X + Y \rightarrow XY$ (fast)
The overall order of the reaction will be