POK 1

1. An ion with a positive electric charge. An atom which has lost one or more electrons.
4. A way of describing the composition of a substances using symbols and numbers
6. substances that undergo chemical change
9. The way chemists write down chemical reactions
10. reaction A chemical reaction that takes in energy
11. reaction A chemical reaction that gives off energy
14. compound A compound made up of ions.
16. The measure of acidity or alkalinity in a substance.
17. energy The energy needed for a reaction to occur
18. An ion with a negative electric charge. An atom which has gained one or more electrons.
19. compound A compound made up of molecules the molecules consist of atoms that are linked by sharing electrons.

1. A substance which alters the speed of a chemical reaction but remains chemically unchanged itself at the end of the reaction.
2. A charged particle an atom or group of atoms which has lost or gained electrons
3. the substances formed as a result of a chemical change
5. A solid which forms and settles in a solution
7. A substance which contains hydrogen that can be replaced by a metal in solution it turns litmus red.
8. The removal of acidity or alkalinity in a substance.
12. The smallest particle of a compound which can normally exist by itself and still have the properties of that substance.
13. A substance containing two or more elements which have been chemically combined.
15. A substance which reacts with an acid to form a salt and water.