Question

For a certain reaction $A$ $\to$ $P$, the for half life for different initial concentration of $A$ is mentioned below

$\left[A_o\right]$	0.1	0.025
$t_{\frac{1}{2}}$ (s)	100	50

Which of the following option(s) is/are incorrect?

• A. The order is 1
• B. The order is 0.5
• C. For $\left[A_o\right]$ = 1M, $t_{\frac{1}{2}}=100\sqrt{10}$ sec.
• D. For $\left[A_o\right]$ = 1M, $t_{\frac{1}{2}}$ = 100sec.

Answer 1

Answer: (A)

The order is 1

Since the half-life equation of a first-order reaction does not include a reactant concentration term, it does not rely on the concentration of reactant present and given by $t_{1/2}=\frac{0.693}{k}$

Here given that half-life varies with concentration, hence option A is incorrect