So for question 1:
The first question asks what the geometry will be when you consider the bonding and nonbonding electrons, or, the bonding and lone pair electrons. To do this, we need to first draw a Lewis dot structure. Cl and F each have 7 valence electrons and O has 6, and there is a net -1 charge so you will have 7(5) + 6 + 1 = 42 valence electrons. Cl is the central atom and O and F form five separate bonds around it. The lewis dot structure will look something like this (sorry this didn't turn out so well. Cl should be in the center with O and F around it):
F -- Cl -- F
However, if you assume that all of the Fs and O have three lone pair (too hard to draw in!), this adds up to only 40 valence electrons. Thus, the Cl must have an additional lone pair:
F -- Cl -- F
We can see from this lewis dot structure, which now correctly has 42 electrons, that the Cl has six groups surrounding it (5 bonds and a lone pair). If you look at the chart you posted above, this is an octahedral.
The second question asks what the actual structure is. Basically, this is just asking what we will see as the structure of the atom. We cannot actually see the lone pair but it still takes up space and impacts the shape of the molecule. The lone pair takes up more room than a bonding pair and therefore decreases the bond angles of the other atoms. The actual structure will be square pyramidal. Look at the chart on this link - it is very helpful:
As you can see, 5 bonding pair and 1 lone pair is a square pyramidal.
The final question asks about the hybridization. Since the LDS shows that this molecule has 6 groups surrounding it (the lone pair counts as a group), it will be d2sp3 hybridized. This hybridization has 6 hybrid orbitals that will accommodate the six orbitals involved in bonding. There's a chart on this site that tells what hybridization goes with what structure:
The second problem is the same thing. Draw the lewis dot structure and use the two tables to determine the actual structure and hybridization. Hope that helps!
· 1 decade ago