Question

The conversion of methyl isonitrile to acetonitrile in the gas phase at 250 °C CH3NC(g)CH3CN(g) is first order in CH3NC with a rate constant of 3.00×10-3 s-1. If the initial concentration of CH3NC is 4.30×10-2 M, the concentration of CH3NC will be 8.30×10-3 M after _____ s have passed.

Answer 1

548s = t

Step-by-step explanation:

A first-order reaction has as general equation:

`ln ([A]_t)/([A]_0) = -kt`

Where
`[A]_t` is the concentration of the reactant in the time t,
`[A]_0` is the initial concentration of the reactant, k is rate constant and t is time. Replacing with values of the problem:

`ln (8.30x10^-3)/(4.30x10^-2) = -3.00x10^-3s^-1*t`

-1.65 = -3.00x10⁻³s⁻¹×t

548s = t

I hope it helps!