Write alpha and beta decay as equations, find the new nucleus from the mass and atomic numbers, and see why gamma and neutron emission change things differently.
What you will learn
- Write and balance alpha and beta decay equations
- Find the mass and atomic number of the new nucleus
- Name the decay from the change in the numbers
- Write and balance positron (beta-plus) decay equations (Edexcel)
The rule: both rows balance
In a nuclear equation the top numbers (mass numbers) add up to the same on both sides, and so do the bottom numbers (atomic numbers).
The radiation is written in the same style:
alpha particle: 42He beta particle: 0−1e neutron: 10n gamma: γ (no numbers)
There is nothing to learn by heart beyond these four symbols. No board gives a nuclear equation on its equation sheet.
The rest of this lesson and its 14 practice questions are locked.
In this lesson
- The rule: both rows balance
- Alpha decay
- Beta decay
- Positron (beta-plus) decay: Edexcel
- Gamma and neutrons
- Try it: The four changes
14 practice questions, marked as you go; about 20 minutes in all.
Key terms
More, Positron, Down, Gamma ray, Neutron
In this unit: Atomic structure and radioactivity
The nuclear atom and how its model developed, isotopes, alpha, beta and gamma radiation, nuclear equations, half-life, the hazards and uses of radiation, and fission and fusion.