Question

Consider a first-order decomposition process
$A _{3} \longrightarrow \frac{3}{2} A _{2}$

A plot of concentration of $A _{3}$ and $A _{2}$ versus time is shown below. At time $t_{ A }$ percentage of reactant composed is

• A. $75 \%$
• B. $50 \%$
• C. $40 \%$
• D. $30 \%$

Answer 1

Answer: (C)

$A_{3} \longrightarrow \frac{3}{2} A_{2}$

$A-x \frac{3}{2} x$

$A-x=\frac{3}{2} x$

or $x=\frac{2}{5} A=40 \%$ of $A .$