Cesium-134 is a β emitter with a half-life of 2.0 years. How much of a 2.50-g sample of cesium-134 will remain after 10 years?

Question

Quizplus · Accepted Answer

After 2 years (one half-life), half of the original cesium-134 will decay, leaving 1.25 g. After 4 years (two half-lives), only a quarter of the original cesium-134 will remain, leaving 0.625 g. Continuing in this manner, we can see that after 10 years (five half-lives), only 1/32 of the original cesium-134 will remain.

To calculate the final amount remaining, we can use the equation:

final amount = initial amount x (1/2)^(number of half-lives)

Plugging in the given values, we get:

final amount = 2.50 g x (1/2)^(5) = 0.078 g

Therefore, the answer is B) 0.078 g.

Cesium-134 Is a β Emitter with a Half-Life of 2