Across
- 2. An electromagnetic radiation of the shortest wavelength and highest energy.
- 3. Number The number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.
- 6. A helium nucleus emitted by some radioactive substances, originally regarded as a ray.
- 8. A fast-moving electron emitted by radioactive decay of substances.
- 9. The center part of an atom which holds the protons and neutrons.
- 13. A chemical element with the same number of protons but with different numbers of neutrons and atomic masses.
- 14. A subatomic particle with a positive electrical charge.
Down
- 1. The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.
- 4. Reaction A chemical reaction or other process in which the products themselves promote or spread the reaction, which under certain conditions may accelerate dramatically.
- 5. The total number of protons and neutrons in a nucleus.
- 7. The time it takes for half of a radioactive substance to decay.
- 10. A nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy.
- 11. A subatomic particle of about the same mass as a proton but without an electric charge.
- 12. A nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.