Question

The gaseous reaction $A_g\to 2B_{(}g)+C_{(}g)$
obeys first order kinetics. The initial pressure is 90 mm and after 10 minutes it is 180 mm. The velocity constant ‘k’ of the reaction is:

• A. $1.15\times {10}^3{s}^{-1}$
• B. $2.30\times {10}^3{s}^{-1}$
• C. $3.45\times {10}^{-3}{s}^{-1}$
• D. $1.15\times {10}^{-3}{s}^{-1}$

Answer 1

The correct option is D $1.15\times {10}^{-3}{s}^{-1}$

$A\to 2B+C$
$P_{i}9000$
$P_t=18090-p2pp$
$180=90-p+2p+p$
by calculating we get $p=45$
$-ln\frac{(P_A{)}_t}{(P_A{)}_0}=kt$
$-ln\frac{45}{90}=k\times 60\times 10$
$k=1.15\times {10}^{-3}{s}^{-1}$