The half-life of a particular isotope of potassium is 1.3 billion years.After 2.6 billion years,how much of the original amount of that isotope remains?
A)Half
B)None
C)One-fourth
D)All of it

Question

Quizplus · Accepted Answer

The half-life of the isotope is 1.3 billion years which means that after 1.3 billion years, half of the original amount of the isotope will remain. After another 1.3 billion years (total of 2.6 billion years), half of that remaining amount will remain, which means only one-fourth (or 25%) of the original amount will be left. Therefore, the correct answer is C) One-fourth.

The Half-Life of a Particular Isotope of Potassium Is 1