Why is plutonium radioactive?

Answer 1

No it does not. There are various types (isotopes) of plutonium. Plutonium 238, the weapons grade material, has a half life of 88 years. Meaning after 88 years half of the material has transforms into another element through radioactive decay.

Plutonium-240 has a half life of ~80 Million years.

But eventually all types of plutonium will decay into other elements.

All radioactive elements will eventually decay into non-radioactive atoms given enough time.

Answer 2

Plutonium is radioactive because it has an unstable nucleus that is trying to achieve a more stable configuration. In order to do this, it emits radiation in the form of alpha particles, beta particles, and gamma rays to reach a more stable state. This process is known as radioactive decay.

Answer 3

Because the ratio number of neutrons/number of protons is too high and the nucleus is unstable.

Answer 4

Depending on the type of the plutonium isotope and the half life.

See the link below.