The concentration of a reactant decreases from $0.2 \ M$ to $0.1 \ M$ in $10 \ \text{minutes}$. The rate of the reaction is

Observe the following reaction: $2 A + B \longrightarrow C$. The rate of formation of $C$ is $2.2 \times 10^{-3} \ mol \ L^{-1} \ min^{-1}$. What is the value of $-\frac{d[A]}{d t}$ (in $mol \ L^{-1} \ min^{-1}$)?

The concentration of a reactant changes from $0.1 \, mol \, L^{-1}$ to $0.095 \, mol \, L^{-1}$ in $10 \, s$. Calculate the rate of reaction.

In a pseudo first order hydrolysis of ester in water,the following results were obtained:

$t \ (s)$	$0$	$30$	$60$	$90$
$[\text{Ester}] \ (mol \ L^{-1})$	$0.55$	$0.31$	$0.17$	$0.085$

What will be the average rate of reaction between the time interval $30 \ s$ to $60 \ s$?

Why is the rate of reaction expressed as negative with respect to a reactant? Is the rate of reaction really negative?

At $298 \ K$ the value of $-\frac{\Delta[Br^{-}]}{\Delta t}$ for the reaction$5Br^-{_{\text{(aq)}}} + BrO_3^-{_{\text{(aq)}}} + 6H^+{_{\text{(aq)}}} \rightarrow 3Br_{2\text{(aq)}} + 3H_2O_{\text{(l)}}$ is $x \ mol \ L^{-1} \ min^{-1}$. What is the rate (in $mol \ L^{-1} \ min^{-1}$) of this reaction?