Answer:
T½ = 16hours
Explanation:
Final mass (N) = 10g
Initial mass (No) = 20g
Time (t) = 16hours
T½ = ?
T½ = In2 / λ
But λ = ?
In(N/No) = -λt
In(10/20) = -(λ * 16)
In(0.5) = -16λ
-0.693 = -16λ
λ = 0.693 / 16
λ = 0.0433
Note : λ is known as the disintegration constant
T½ = In2 / λ
T½ = 0.693 / 0.0433
T½ = 16hours
The half-life of the sample is 16hours