Nuclear Reactions

Nuclear Reactions are a change in the nucleus and can change the atom into another. They often occur when unstable nuclei want to be stable. Nuclei undergo spontaneous changes in their number of protons and neutrons until they are stable.

Radioactive Isotopes are unstable and go through radioactive decay, or ejecting or emitting pieces from the atom to achieve stability. Some types of radioactive decay are:

• Alpha decay- ejection of an alpha particle from the nucleus
• Beta decay- ejection of a beta particle from the nucleus

Alpha Decay:

• Alpha particle (α) consists of two protons and two neutrons
• It is the same as the nucleus of a helium atom
  • 238/92 U ------> 234/90 Th + 4/2 He (α) + (γ) 

Beta Decay:

• A beta particle (β) is an electron ejected from the nucleus of the atom
• Electrons do not exist by themselves within the nucleus- a neutron can split into two parts, becoming an electron and a proton. The electron is ejected and the proton

  stays behind in the nucleus.

  • 14/6 C ------> 14/7 N + 0/-1 e (β) + (γ)

Gamma Rays (γ):

Gamma rays (γ) are a kind of radiation similar to light, microwaves, and x-rays except they are much higher in energy, so they can be very dangerous. When gamma rays are emitted, the identity of the emitting atom does not change. Gamma rays accompany alpha and beta decay and also fission.

Half Life:

Half life is the time required for a radioisotope to decay to half (½) of its original amount. Each radioisotope has its own half life. Half lives range from nanoseconds to billions of years. The shorter the ½ life, the more energetic (unstable)