Question

Consider a certain reaction A → Products with k = 20 x 10^-2 s^-2. Calculate the concentration of A remaining after 100 s if the initial concentration of A is 1.0 mol L^-1.

Answer 1

k = 20 x 10^-2 s^-1
[A]₀ = 1.0 mol L^-1
t = 100s
[A] = ?

–log [A] = 0.8684
log[A] = – 0.8684
[A] = Antilog (-0.8684)
or [A] = Antilog (1.1316)
[A] = 0.1354 mol L^-1
Hence after 100s, the remaining amount of concentration will be 0.1354 mol L^-1