First of all, how do polar bonds cancel each other?? An easy example would really help alot 
And in the case of hybrid orbitals, how does hybrid orbitals with BeF2 work out? Could anyone explain the concept of this hybrid orbital and how really BeF2 forms a bond, though Be doesnt have any electrons in P orbital?
And finally, what are pi/sigma bonds, and how would you find them?
Thanks! Even if you can only help me with one question, I would really appreciate it.
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With accordance to the second question,
how would sp3 be the hybrdization for phosphorous in PH3?

And in the case of hybrid orbitals, how does hybrid orbitals with BeF2 work out? Could anyone explain the concept of this hybrid orbital and how really BeF2 forms a bond, though Be doesnt have any electrons in P orbital?
And finally, what are pi/sigma bonds, and how would you find them?
Thanks! Even if you can only help me with one question, I would really appreciate it.

-------
With accordance to the second question,
how would sp3 be the hybrdization for phosphorous in PH3?