# Answers to Periodic Table and Simple Ionic Compounds

1. Complete the following Table:
 Symbol Atomic Number Mass Number Number of Protons Number of Neutrons Number of Electrons Net Charge $$\mathrm{^{34}_{16}Se^{2-}}$$ 16 34 16 18 18 -2 $$\mathrm{^{51}_{23}V^{3+}}$$ 23 51 23 28 20 +3 $$\mathrm{^{40}_{20}Ca^{2+}}$$ 20 40 20 20 18 +2
1. Would you expect each of the following atoms to gain or lose electrons when forming ions? What ion is the most likely in each case?
1. K should lose one electron to form K+
2. F should gain one electron to form F
3. Ca should lose two electrons to form Ca2+

1. Fill in the following table:
 Name Symbol Group Period Metal, nonmetal or metalloid? transition metal or main group? sodium Na 1 3 metal main group iron Fe 8 4 metal transition metal oxygen O 16 2 nonmetal main group
1. Give the formulas for the ionic compounds made of the following ions:
1. ScBr3
2. K2O
3. CaI2
4. Cr2S3
5. RbF
6. MgO
7. K3N
8. SrF2
9. Al2S3