Question

H₃PO₃ can be represented by structures 1 and 2 shown below. Can these two structures be taken as the canonical forms of the resonance hybrid representing H₃PO₃? If not, give reasons for the same.

Answer 1

Hello friend !!

Well in organic chemistry canonical structure are those which involves only the movement of pi electrons or lone pair or negative charge where there is conjugation and it doesn't involve the movement of any atom .

While here in the figure Hydrogen was bonded with Phosphorous in figure 1 while in figure 2 hydrogen is bonded with oxygen .

Thus involving the change in position of atom which doesn't contribute to the canonical forms

Hope this helps!!  ^_^