The velocity constant of a first-order reaction is expressed in the units:

$20 \%$ of a first order reaction was found to be completed at $10:00 \ am$. At $11:30 \ am$ on the same day,$20 \%$ of the reaction was found to be remaining. The half-life period in minutes of the reaction is

Consider a certain reaction $A \rightarrow \text{Products}$ with $k = 2.0 \times 10^{-2} \ s^{-1}$. Calculate the concentration of $A$ remaining after $100 \ s$ if the initial concentration of $A$ is $1.0 \ mol \ L^{-1}$.

The half-life of a first order reaction $X \to Y$ is $100 \ min$. The concentration of $X$ would be reduced to $10 \%$ of the initial concentration in .......... $min$.

Consider the following first-order gas-phase reaction: $A_{(g)} \to B_{(g)} + C_{(g)}$. At time $t$,the total pressure is $p_t \ atm$. Derive the integrated rate equation for this reaction.

Identify True $(T)$ and False $(F)$ statements for the following first order reaction $R \rightarrow P$:
$1. t_{1/2} = \frac{0.693}{2k}$
$2. t_{1/2} \propto k$