Chemistry Vocabulary

4. Electrons in the outermost shell of an atom
9. The least reactive group on the periodic table
10. An atom that has lost or gained one or more electrons
11. The smallest part of an atom
12. The results of a chemical reaction
14. Substance used to cause a chemical reaction
15. Elements that have the same atomic number but different number of neutrons
16. The smallest unit of matter that forms an element

1. Where the protons and neutrons are found in a atom
2. The most reactive group of metals on the periodic table
3. The part of the atom with a positive charge
5. A substance made of atoms that all have the same number of protons
6. The base unit of amount of a substance as determined by the International System of Units
7. A substance composed of two or more chemical elements
8. The heaviest part of an atom
13. The study of substances and their behaviors