1. Isotopes and Ions

2. Isotopes Atoms of the same element that have different masses Have the same number of protons and electrons but different numbers of neutrons

3. How many protons, neutrons, & electrons are in the following? Bromine – 80 Write the hyphen notation for the element that contains 15 electrons and 15 neutrons 13 C 6 35 p, 35 e, 45 n Phosphorus (P) – 30 6 p, 6 e, 7 n

4. Ions An atom or group of bonded atoms that has a positive or negative charge Positive ions have lost electrons. They have more protons than electrons. Ex: Ca 2+ Negative ions have gained electrons. They have more electrons than protons. Ex: N 3-

5. How many protons, neutrons, and electrons are in the following: Na + Cl - Mg 2+ O 2- Al 3+ 11 p, 12 n, 10 e 17 p, 18 n, 18 e 12 p, 12 n, 10 e 8 p, 8 n, 10 e 13 p, 14 n, 10 e