In the Lewis structure for FeF3, how many lone pairs surround the iron atom? NEED ASAP
Select one:
a. 0
b. 1
c. 2
d. 3
Clear my choice

b. 1

Explanation:

If we consider it carefully we will notice that the electronic configuration of iron III is; [Ar] 3d5 4s0.

Now, three electrons from the d orbital are paired with the three electrons from three F atoms according to the valence bond theory. This leaves out one pair of electrons localized on the d orbital of iron.

Hence the compound has one lone pair of electrons.

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.