Chemistry crossword

4. matter that exist as a solid,liquid or gas
5. substance that helps a chemical reaction to proceed more quickly
6. vertical column of elements in the periodic table
8. positively charged part of an atom
9. the smallest part of an element that is representative of that element
10. an experiment in which all reactants and all the products of a chemical reaction are all accounted for
11. chemical reaction that absorbs heat energy
13. groups of atoms acting as one
15. change in the appearance or state of a substance that does not change the compositions
17. compound with a metal and a non metal combined
18. positively charged particle in the nucleus of an atom
19. group 17 elements in the periodic table
20. chemical reaction that releases heat energy
22. characteristic that that describes a particular substance
24. atom that has become a electrically charged because it has lost or gained electrons

1. the materials at the start of the reaction
2. invisible negativity charged particle that orbits the nucleus of an atom
3. element that has both metallic and non-metallic properties
7. the materials produced by the reaction
10. change that results when two or more substances react to create a different substance or substances
12. slow chemical change that occurs when oxygen in the air reacts with a metal
14. an experiment in which one or more products of a chemical reactions can escape
16. chemical reaction that occurs when oxygen reacts with a substance to form a new substance and give off energy
21. chemical combination of two or more elements in a specific ratio
23. table a table in which the element are organized