The reaction CH3Cl + OH- CH3OH + Cl- is first order in both chloromethane and hydroxide.

Question:

The reaction CH3Cl + OH- → CH3OH + Cl- is first order in both chloromethane and hydroxide.
Given the rate constant k = 3.5 × 10-3 mol L-1 s-1, what is the observed rate at the following concentrations?
[CH3Cl] = 0.50 mol L-1 [OH-] = 0.015 mol L-1
(a) 2.6 × 10-5 mol L-1 s-1
(b) 2.6 × 10-6 mol L-1 s-1
(c) 2.6 × 10-3 mol L-1 s-1
(d) 1.75 × 10-3 mol L-1 s-1
(e) 1.75 × 10-5 mol L-1 s-1