Matilda has a 100 g rock sample. She knows that the rock contains uranium-238 and that the half-life of uranium-238 is 4.5 X 109 years. If she cuts the rock sample in half, what happens to the half-life of the uranium?

Question

The half-life increases.
The half-life decreases.
The half-life remains the same.

Answer 1

The half-life of a radioactive isotope, such as uranium-238, is a characteristic property of that isotope and does not change regardless of the amount of the sample. Therefore, when Matilda cuts the 100 g rock sample in half, the half-life of the uranium-238 within it remains the same.

So the correct answer is: The half-life remains the same.