Question

(a) What are radioactive isotopes? Give two ex­amples.

Answer 1

Radioactive isotopes:

1. The isotopes whose nuclei are unstable and dissipate excess energy by spontaneously emitting radiations in the form of alpha, beta and gamma rays are known as radioactive isotopes.
2. All chemical element has one or more radioactive isotopes.
3. There are more than $1,000$ radioactive isotopes known.
4. There are $50$ radioactive isotopes in nature and the rest are made artificially.

Examples of radioactive isotopes:

1. Carbon$-14$
2. Arsenic$-74$
3. Sodium$-24$
4. Iodine$-131$