Across
- 2. weighted average mass of the atoms in a naturally occurring sample of the element.
- 4. species of atom as characterized by the number of protons, the number of neutrons, and the energy state of the nucleus.
- 5. the mass in grams of 1 mole of the substance.
- 9. used to express atomic and molecular weights
- 11. the number of atoms or molecules in one mole of a substance
- 12. states that if two elements form more than one compound, then the ratios of the masses of the second element which combine with a fixed mass of the first element will always be ratios of small whole numbers.
Down
- 1. states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations.
- 3. sometimes called Proust's law, or law of constant composition
- 5. base unit of amount of substance in the International System of Units.
- 6. the total number of protons and neutrons in a nucleus.
- 7. number found on the top left of an element on the periodic table.
- 8. strong attractive force between nucleons in the atomic nucleus that holds the nucleus together.
- 10. one of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table.
- 11. smallest unit of ordinary matter that forms a chemical element.