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Hi. I'm having some difficulty with some of my homework questions. Choose all that apply

1. Consider the related molecules POF₂^- and POF₃. What is correct for both molecules....
A) The P atom is sp3-hybridised.
B)The F-P-F bond angle will be approximately 109.5 degrees.
C) Geometry around the P centre is tetrahedral
D) Number of valence electrons for the molecule is 28.
E) Bonds between the p and O are sigma and a pi bond.
F) minimised formal charge on P is 0.

I've elminated C and D and F.
For B) I'm not to sure because so far I've only been taught VSEPR where the ligands are the same. I have more questions to come.

please *delete me*
Will be much appreciated.

QUESTION 2:
Which of the following species has an unpaired electron?
A0 None
B) NO₂
C)NO₂<sup>+[/sup
D) NO₂-
E) NO+

Right now I'm gunning for NO₂ but it confuses me because it doesrn't really follow the octet rule.

QUETSION 3) OK. I think this is a horrible question.
What can you change when drawing resonance structures?
A) Total number of protons
B) Total number of atoms
C) Total number of bonds
D) Total number of electrons and atoms
E) Total number of electrons.
I'm going to C but that doesn't really seem correct.</sup>