Across
- 2. a group of two or more atoms that form the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance.
- 3. a chemical change that occurs when two or more substances combine to form a new substance.
- 7. in a chemical reaction mass is neither created nor destroyed.
- 8. formed by the equal sharing of electrons from both participating atoms.
- 12. a particle of matter that uniquely defines a chemical element.
- 13. regions around the nucleus in which electrons move according to their energies.
- 14. a character, usually a letter or number, that's printed slightly below and to the side of another character.
- 16. a substance that is present at the end of a chemical reaction.
Down
- 1. the bond formed by the complete transfer of valence electron to attain stability
- 4. an electron of an atom, located in the outermost shell (valence shell ) of the atom, that can be transferred to or shared with another atom
- 5. an atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons
- 6. is the number in front of the formula
- 9. a substance whose atoms all have the same number of protons:
- 10. a material composed of two or more components
- 11. the tendency of atoms to prefer to have eight electrons in the valence shell.
- 15. a substance that changes when it is combined with another substance in a chemical reaction.