The rate constant for a certain reaction is k = 6.30*10-3 s-1. If the initial reactant concentration was 0.500 M, what will the concentration be after 19.0 minutes? Express your answer with the appropriate units.

Answer: 0.059M

Explanation: time.

t = 19minutes

t = 19 * 60 s

t = 140s

k = n/delta t

(where n is the ratio of change in concentration while delta t is the change in time)

k = n/dt = 6.30*10-3 s-1

6.30*10-3 s-1 = dc/140s

n = 6.30*10-3 s-1 * 140s

n = 882 * 10-3

= 0.882

Concentration of reactant used in forming a product in the reaction after 19 minutes =

n * concentration

0.882 * 0.5 = 0.441M

Reactant concentration

= (0.5 - 0.441) M

= 0.059M