F.3 Chem Question~~~~{plz!! URGENT!!!}~~~~

a)
Q and R would form an ionic compound.


b)
A metal and a non-metal form an ionic compound.

The electron arrangement of O is 2, 8.
O has 8 electrons in the outermost shell.
Hence, O is a noble gas and seldom forms compounds.

The electron arrangement of P is 2, 8, 4.
P has 4 electrons in the outermost shell.
Hence, P is a non-metal, but it is hardly to form ionic compounds (because it is hardly to gain or lose 4 electrons in the outermost shell).

The electron arrangement of Q is 2, 8, 7.
Q has 7 electrons in the outermost shell.
Hence, Q is a reactive non-metal, which can react with metals to form ionic compounds readily.

The electron arrangement of R is 2, 8, 8, 1.
R has 1 electron in the outermost shell.
Hence, R is a reactive metal, which can react with non-metals to form ionic compounds readily.
=