Across
- 7. catalyst involved in chemical reactions in living things
- 8. substance made of only one kind of matter, which has a unique set if properties
- 10. invisible negatively charged particle that orbits around the nucleus of an atom
- 14. change in the appearance or state of a substance that does not change the composition
- 15. descriptions of a substance that can be pounded or rolled into sheets
- 17. chemical reaction that releases energy
- 18. pure substance formed when non-metals combine
- 20. change that results when two or more substances react to create a different substance or substances; the new substances have completely different properties from the original ones
- 21. atoms that have become electrically charged because it has lost or gained electrons
- 22. change of state from solid to a gas or from a gas to a solid
- 24. pure substances formed when at least one metal or non-metal combine
- 25. positively charged particle in the nucleus of an atom
Down
- 1. neutral particle in the nucleus of an atom
- 2. chemical combination of two or more elements in a specific ratio
- 3. anything that has mass and occupies space
- 4. pure substance that cannot be broken down into other substances; a substance made up of only one type of atom
- 5. combination of pure substances; unlike a compound, the components of a mixture do not combine chemically and are not always in the same ratio
- 6. group 18 elements in the periodic table; the most stable and nonreactive elements
- 9. chemical reaction that absorbs energy
- 11. number of protons in the nucleus of one atom of an element
- 12. positively charged that centre of an atom; contains protons and neutrons
- 13. shiny, malleable, ductile element that conducts electricity
- 16. property that describes the physical appearance and composition of a substance
- 19. substance that strongly resists the flow of electricity
- 23. vertical column of elements in the periodic table; elements in a family all have similar chemical properties; also called a family