Nuclear Equations

Basics of Nuclear Equations:

• Nuclear equations represent the changes in the nucleus during radioactive decay.
• Atomic and mass numbers must be conserved in nuclear equations. This means the total atomic and mass number on each side of the equation must be equal.
• In these equations, the parent nuclide (the atom before decay) decays to produce a daughter nuclide (the atom after decay) and a particle (either alpha, beta or gamma).

Alpha Decay:

• Alpha decay involves the loss of an alpha particle (an He^2+ ion).
• An alpha particle is made up of 2 protons and 2 neutrons, so it is symbolised by ^4/2 He.
• In alpha decay, the mass number of the parent nuclide decreases by 4, and the atomic number decreases by 2.

Beta Decay:

• Beta decay involves the loss of a beta particle (an e^- ion).
• A beta particle has a charge of -1, so it’s written as ^0/-1 e in nuclear equations.
• In beta decay, the mass number stays the same, but the atomic number increases by 1 as a neutron turns into a proton.

Gamma Decay:

• Gamma decay involves emission of a gamma photon, a packet of electromagnetic energy.
• Gamma radiation has no mass or charge, so its symbol, γ, has atomic and mass numbers of 0.
• In gamma decay, the nucleus simply loses energy, so the atomic and mass numbers remain the same.

Positron Emission:

• Positron emission occurs when a proton turns into neutron and emits a positron (an e^+ ion).
• A positron is a positively charged beta particle, represented by ^0/+1 e in equations.
• In positron emission, the mass number remains the same, but the atomic number decreases by 1.

By understanding nuclear equations, you can identify the type of decay, calculate the change in atomic and mass numbers, and predict the identity of daughter nuclides.