periodic table

2. electrons on the outermost energy level of an atom
4. the possible locations around a nucleus where electrons may be found
6. the average mass of all the isotopes of an element
7. uses dots to represent valence electrons around an elements atomic symbol
9. a chemical bond formed when atoms share two pairs of electons
14. a table that shows the elements, their atomic number, symbol, and average atomic mass; elements with similar chemical properties are grouped together
15. a pure substance made of only one kind of atom
18. a chemical bond formed when atoms share electons
19. the smallest part of an element that still has the same properties as the element
21. a chemical bond formed when atoms share 3 pairs of electrons
22. positively charged particles located in the nucleus of an atom

1. created in an atom when it has more protons than electrons
3. the central part of the atom where protons and neutrons are located
5. a chemical bond formed when atoms atoms share one one pair of electrons
8. the smallest particle of a compound that retains all the properties of the compound and it is composed of one or more atoms
10. negatively charged particles located outside the nucleus of an atom
11. the number of protons in the nucleus of an atom
12. created in an atom when it has more electrons than protons
13. particles of no charge located in the nucleus of an atom
16. atoms of the same element that have different numbers of neutrons
17. a chemical bond resulting from the attraction between oppositely charged ions
20. a charged atom due to loss or gain of negative electrons