Across
- 3. the central and most important part of an object
- 6. a helium nucleus emitted by some radioactive substances
- 8. each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei
- 10. number is the number of protons in the nucleus of an atom
- 11. interval of time required for one-half of the atomic nuclei of a radioactive sample to decay
- 12. a subatomic particle of about the same mass as a proton but without an electric charge
- 13. a series of events so related to each other that each one initiates the next
Down
- 1. The mass number also called atomic mass number or nucleon number, is the total number of protons and neutrons
- 2. this is a partical for which the mass number will not change but the atomic number increases by one
- 3. a nuclear reaction in which a heavy nucleus splits spontaneously
- 4. the emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.
- 5. Gamma rays are a form of electromagnetic radiation
- 7. Nuclear fusion is the process by which two light atomic nuclei combine to form a single heavier one while releasing massive amounts of energy.
- 9. a stable subatomic particle occurring in all atomic nuclei