Question

Compare the formulas of the oxides formed by the alkaline earth metals with those of lead.

Answer 1

Electronic configuration tells you how an element will react and what it will be react with and how many electrons it will lose in the process.
just compare an alkali earth and a lead oxide

eg)
Na1+ + H20 > NaOH

can you see that the alkaline earth becomes neutral when it oxidizes and forms a salt

eg2)
Pb + H20 > PbO + H2

With lead its oxidization does not include the hydrogen element and therefore does not form a salt. This is because instead of becoming a neutral ion it gains the charge of oxygen and becomes 2-