How do you find the rate of reaction given the rate constant and concentrations if you don’t have the time?

1 Answer
Aug 21, 2017

You don't need the time. We take by convention the reaction rate as the initial rate #r_i(t) ~~ r(t)#, i.e. the rate at time zero,

#overbrace(r(t))^("rate") = overbrace(k)^"rate constants"overbrace([A]^m[B]^n)^" concentrations"#,

(where #m# and #n# are reaction orders with respect to each reactant, and #k# is the rate constant)

for the general reaction

#nu_A A + nu_B B -> nu_C C + nu_D D#,

where #nu# is the stoichiometric coefficient, #A# and #B# are reactants, and #C# and #D# are products.

The rest of the process depends on the problem, but this is usually where you would start, as the reaction rate usually decreases over time.