Question

what differs between a radioactive isotope and a stable isotope of the same element?

radioactive isotopes last for less time.

stable isotopes are usually heavier.

radioactive isotopes do not break down.

stable isotopes break down quickly.

Explanation:

Stable isotopes do not decay over time, while radioactive isotopes are unstable and decay, emitting radiation. This means radioactive isotopes have a limited lifespan due to decay, so they last for less time compared to stable isotopes.

Answer:

Radioactive isotopes last for less time.