In the following pairs of binary compounds determine which one is a molecular substance and which one

Question:

In the following pairs of binary compounds determine which one is a molecular substance and which one is an ionic substance. Use the appropriate naming convention (for ionic or molecular substances) to assign a name to each compound:
(a) SiF4 and LaF3,
(b) FeCl2 and ReCl6,
(c) PbCl4 and RbCl.