Fill in the table below.
Name __________________________________
Name
Symbol
Atomic
Number
Mass
Number
Protons
Electrons
Neutrons
lithium
209 Pb
25
28
202
74
122
113
56
85
Iodine 131
236 U
Atoms are neutral, meaning that the number of protons equals the number of electrons. Atoms that have
charges are called ions. Positive ions mean that the electrons have been lost. Negative ions mean that
electrons have been gained. Use this information to fill in the following chart.
Name
Symbol
sodium
ion
Atomic
Number
Mass Protons Neutrons Electrons
Number
11
10
Ca 2+
sulfide
nitride
16
N 3-
18