All of the following species would be expected to be able to function a Lewis bases EXCEPT
a. F-
b. O2-
c. OH+
d. H2O
BF3
  ..     -
:F:
  ..
Lewis bases can donate electrons, as in the case of F^- there are 4 pairs of electrons available for the donation. Now look at the others and see if they can do that.
To determine which species would not function as a Lewis base, we need to understand what a Lewis base is. A Lewis base is a molecule or ion that can donate an electron pair to form a covalent bond.
To identify a Lewis base, we should consider the electronic configuration and the availability of lone pairs of electrons. Elements from Group 17 (the halogens) are generally good Lewis bases because they have one valence electron and can easily donate it to form a bond. Oxygen forms stable double bonds and can act as a Lewis base by donating a lone pair of electrons.
Now, let's evaluate each of the given options:
a. F-: Fluorine is a halogen and tends to readily accept electrons to complete its octet. It can act as a Lewis base by donating its lone pair of electrons. Therefore, F- is a Lewis base.
b. O2-: Oxygen can form stable double bonds, and in the case of O2-, it has two extra electrons, so it has two lone pairs available for donation. Therefore, O2- can act as a Lewis base.
c. OH+: Hydroxide ion (OH-) is well-known for acting as a Lewis base by donating its lone pair of electrons. However, the given option is OH+ which indicates the loss of an electron. Hydroxide ion loses an electron to form OH+. Losing an electron makes it a Lewis acid, not a Lewis base. Therefore, OH+ is not a Lewis base.
d. H2O: Water is known to form hydrogen bonds, which result from oxygen donating a lone pair of electrons. Oxygen in water can act as a Lewis base, making H2O a Lewis base.
e. BF3: Boron trifluoride (BF3) is a compound where boron is surrounded by three fluorine atoms. Boron has an empty p-orbital, so it can accept a pair of electrons, making Boron trifluoride a Lewis acid, not a Lewis base.
In conclusion, among the given options, OH+ (choice c) would not be expected to function as a Lewis base.