Across
- 3. The basic unit of matter consisting of a nucleus surrounded by electrons.
- 9. The antimatter counterpart of the neutrino, emitted during beta minus decay.
- 11. A fundamental particle that combines with other quarks to form protons and neutrons.
- 12. The antimatter equivalent of an electron; it has the same mass as an electron but a positive charge.
- 14. The dense central region of an atom containing protons and neutrons.
- 17. A collective term for the particles found in the nucleus: protons and neutrons.
- 18. An uncharged particle found in the nucleus of an atom.
- 21. A particle with no charge and extremely small mass emitted during beta plus decay.
- 22. Radiation High-energy electromagnetic radiation emitted from an excited nucleus.
- 23. Quark A type of quark with a charge of +2/3 that is found in protons and neutrons.
- 24. Plus Particle A positron emitted when a proton changes into a neutron.
Down
- 1. Particle A particle consisting of two protons and two neutrons, equivalent to a helium nucleus.
- 2. Decay The process by which an unstable nucleus transforms into a more stable nucleus by emitting radiation.
- 4. Stability The condition in which a nucleus remains intact because the strong nuclear force balances proton repulsion.
- 5. A negatively charged particle that exists outside the nucleus.
- 6. Repulsion The force that causes positively charged protons to repel one another.
- 7. A positively charged particle found in the nucleus of an atom.
- 8. Quark A type of quark with a charge of –1/3 that is found in protons and neutrons.
- 10. The spontaneous emission of radiation from an unstable nucleus.
- 13. Nuclear Force The powerful attractive force that holds protons and neutrons together in the nucleus.
- 15. of Charge The principle that total electric charge remains the same before and after a nuclear reaction.
- 16. A specific type of nucleus characterised by its number of protons and neutrons.
- 19. Minus Particle A high-speed electron emitted when a neutron changes into a proton.
- 20. Atoms of the same element that have the same number of protons but different numbers of neutrons.
