3) In 5 electron group molecules, what is the difference between axial and equatorial positions? Which groups are removed as lone pairs are added?

The axial positions the bond angle is 120 degrees and in equatorial positions the bond angle is 90 degrees.

Functional groups on central atom gets reduce if lone pairs are added.

Explanation:

The number of lone pairs and base pairs of electrons tells the geometry of the molecule.

VSEPR Theory helps to know the lone pairs and bond pair electrons on the centre atom of the molecule.

Example of molecule containing 5 electron pairs can have four bond pairs and 1 lone pair.

eg: Cl

the repulsion is shown as

lp-lp> lp-bp>bp-bp

These are in equatorial position because of the repulsion of lone pairs.

It can have 2 lone pairs and 3 bond pairs. eg. Xe

Lone pairs in this is also in equatorial position as

lp-lp> lp-bp> bp-bp

In axial positions the bond angle is 120 degrees

in equatorial positions the bond angle is 90 degrees, due to the repulsion in  lone pair of electrons.

If 1 lone pair is there it can be replaced by bonding with hydrogen.

If 2 lone pairs are there then bonding with oxygen is there. The covalent bond is formed.

i think it's c. i'm not sure but i think so.