Radioactivity

Question 1

Beta decay

Answer 1

Emission of a beta particle (B- ; a high speed electron) due to excess neutrons. A neutron is converted to a proton and a the B- is ejected to balance the charge.

Question 2

Positron decay

Answer 2

Emission of a positron (B+ ; a positively charged electron) due to excess protons. A proton is converted to a neutron and a the B+ is ejected to balance the charge.

Question 3

Electron capture

Answer 3

An inner atomic electron is absorbed into the nucleus, combining with a proton to form a neutron; due to excess protons

Question 4

Neutron emission

Answer 4

A neutron is ejected from the nucleus due to excess neutrons

Question 5

Gamma decay

Answer 5

Usually follows other forms of nuclear decay (alpha and beta); daughter nuclei are in an excited state emit a gamma ray.

Question 6

Alpha decay

Answer 6

Emission of an alpha particle (2 protons 2 neutrons i.e. a helium nucleus) due to a large atomic mass