Question

In a first-order reaction, the initial concentration of A is 0.40 M. What is the concentration of A after 15 seconds if the half-life of the reaction is 3 seconds

Answer 1

Answer:

0.0125M

Explanation:

yess! i love half life reactions!

half life equation: $N_o(\frac{1}{2} )^\frac{t}{t_\frac{1}{2} }$

so basically, the initial amount is N_o

t_1/2 is the half life

and t is the time

0.40(1/2)^15/3= 0.0125M