How much of compound A will remain after 2 ​hours? How long will it take until 0.10 M of compound A​ remains?

Question

Reacting with water in an acidic solution at a particular​ temperature, compound A decomposes into compounds B and C according to the law of uninhibited decay. An initial amount of 0.50 M of compound A decomposes to 0.45 M in 30 minutes.

Answer 1

0.45 = 0.50e^0.5r (30 minutes is 0.5 hour)

0.9 = e^0.5t

ln 0.9 = 0.5t

Can you solve for t and then determine amount after 2 hours?