Question - Part A
You are using a Geiger counter to measure the activity of a radioactive substance over the course of several minutes. If the reading of 400. counts has diminished to 100. counts after 36.9minutes , what is the half-life of this substance?
Part B
An unknown radioactive substance has a half-life of 3.20hours . If 11.1g of the substance is currently present, what mass A0 was present 8.00 hours ago?
Express with the appropriate units.
Explicate the each step. Explicate the process and each step.