For the reaction `3A(g)overset(k)toB(g)+C(g)` k is `10^(-4)L//mol.min`.
If [A] = 0.5M then the value of `-(d[A])/(dt)`(in `ms^(-1)` is:

Options

A. `7.5 xx 10^(-5)`
B. `3 xx 10^(-4)`
C. `2.5 xx 10^(-5)`
D. `1.25 xx 10^(-6)`

Answer

D

Explanation

Reaction is second order, `k=10^(-4) L // mol. min.`
`:. -(1)/(3)(d[A])/(dt)=k[A]^(2)`
`-(d[A])/(dt)=10^(-4) xx 3 xx (0.5)^(2)`
`=7.5 xx 10^(-5) M min^(-1)`
`=(7.5 xx 10^(-5))/(60)=1.25 xx 10^(-6) Ms^(-1)`