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.

548s = t

Explanation:

A first-order reaction has as general equation:

Where is the concentration of the reactant in the time t, is the initial concentration of the reactant, k is rate constant and t is time. Replacing with values of the problem:

-1.65 = -3.00x10⁻³s⁻¹×t

548s = t

I hope it helps!

the answer is 1 i believe