Question

The concentration of R in the reaction $R\to P$ was measured as a function of time and the following data is obtained.

[R] in M	1.0	0.75	0.40	0.1
t in minute	0.0	0.05	0.12	0.18

The order of reaction is:

Answer 1

$a-x$	$0.75$	$0.4$	$0.1$
$\Delta x$	$-0.25$	$-0.6$	$-0.9$
$rate=-\frac{\Delta x}{\Delta t}$	$-\frac{-0.25}{0.05}=5$	$-\frac{-0.6}{0.12}=5$	$-\frac{-0.9}{0.18}=5$

Since $rate=-\frac{\Delta x}{\Delta t}=constant$ for different concentration values, so the reaction is of zero order.