Mass after 60 years:
2 kg of cesium-137 will remain after 60.0 years.
What is Half-life?
The duration needed for a quantity to decrease to half of its initial value is known as the half-life.
Given:
N0 = is the initial amount of cesium-137 = 8.0 Kg
N = is the amount remaining after a time = Unknown
t = Duration of cesium-137 decay in 8.0 Kg = 60 years
t1/2 = half-life of cesium-137 = 30.0 years
Formula = N/No = (1/2)^t/t1/2
After putting the value:
N/8= (1/2)^60/30
N/8= (1/2)^2
N/8= 1/4
4N= 8
N= 8/4
N= 2 Kg
As a result, 2 Kg of cesium-137 will be present after 60 years.
Learn more about the half-life here,
https://brainly.com/question/14018709
#SPJ4