Radioactive Decay

When unstable isotopes try to balance themselves by getting rid of their excess protons or neutrons

Chemical vs Nuclear Reactions

Chemical

• The interaction of substances to form new substances
• The identities of the elements do not change; only their organization changes

Nuclear

• Involve changes in the nucleus of an atom, sometimes resulting in new elements

• The nucleus of an atom contains protons (+) and neutrons (0)
• The positively-charged protons repel each other (electrostatic forces)
• However, the nucleus is held together by the strong nuclear force which is always attractive and much stronger than electrostatic forces

Unstable Isotopes

• Atoms with too many protons or too many neutrons, upsetting the strong nuclear forces
• Try to balance themselves by getting rid of their excess protons or neutrons
• Unstable nuclei are radioactive and emit Radiation

Radiation

The emission of Energy in the form of waves or fast-moving particles The higher the frequency of an electromagnetic-wave, the more energy it carries

Ionizing Radiation (Gamma, X-Ray)

Waves or particles that carry enough energy to remove an electron from an atom or molecule

Types of Radioactive decay

Alpha Decay

It is the most common form of decay. A helium nucleus (two protons and two neutrons) is spontaneously emitted from the nucleus ${}_Z^{A}X{\to }_{Z-2}^{A-4}Y{+}_2^{4}He$

Beta Declay

Beta-Negative Decay

• When a nucleus contains too many neutrons, the strong nuclear force becomes much greater than the   electrostatic force - A neutron will spontaneously decay into a proton and electron to maintain stability
• An electron is emitted from the nucleus of a parent atom ${}_Z^{A}X{\to }_{Z+1}^{A}Y{+}_{-1}^{\text{0}}e$

Beta-Positive Decay

• A proton changes into a neutron and a positron (a particle with a positive charge and the same mass as an electron ${}_Z^{A}X{\to }_{Z-1}^{A}Y{+}_{+1}^{\text{0}}e$

Electron Capture

An electron is absorbed by a nucleus and combines with a proton to form a neutron Mass stays the same but a proton is lost ${}_Z^{A}X{+}_{-1}^{\text{0}}e{\to }_{Z-1}^{A}Y$

Gamma Decay

• After a nuclear reaction has occurred, the daughter (new) nucleus is an a high-energy (excited) state
• The nucleus spontaneously releases energy (gamma ray) to return to a lower, more stable energy state ${}_2^{3}H{e}^{\star }{\to }_2^{3}He{+}_0^0\gamma$

Gamma ray

highly energetic form of electromagnetic radiation emitted as a photon (high energy particle with no mass)