360Science™: Natural Radiation

In this lab students are investigating potassium-40. Potassium, one of the most abundant minerals on Earth, is present in most foods and is an essential element in the human body. It is also a major source of natural radiation. Students start by filling in a chart of their natural radiation exposure and compare that to the average exposure in the U.S. They then use a radiation detector to measure the activity of a 2 gram mass of potassium chloride.