Consider the following hydrolysis reactions: AsCl3 + excess H2O gives an oxyacid and a hydroacid. PCl3 + excess H2O gives an oxyacid and a hydroacid. PCl5 + 1 mole H2O gives an unknown product Z and HCl. The ratio of the number of pi bonds to the number of sigma bonds in compound Z is:

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1:5. PCl5 + H2O (1 mole) gives POCl3 (Z) + 2HCl. In POCl3: there is 1 P=O double bond (1 pi bond + 1 sigma bond) and 3 P-Cl single bonds (3 sigma bonds), plus the sigma component of P=O. Total sigma bonds = 1 (P=O sigma) + 3 (P-Cl) = 4, plus the coordinate/dative bond can be counted as 1 sigma = total 4 sigma bonds from P centre. Actually counting: P=O has 1 sigma + 1 pi; 3 x P-Cl each has 1 sigma. Total sigma = 4, total pi = 1. Ratio pi:sigma = 1:4. However treating the P=O as a coordinate bond (dative bond, counts as sigma), ratio is 0:4 = not listed. Using the standard Lewis structure with P=O double bond: 1 pi bond, 4 sigma bonds (1 in P=O + 3 in P-Cl). Ratio = 1:4. But considering all b

Consider the following hydrolysis reactions: AsCl3 + excess H2O gives an oxyacid and a hydroacid. PCl3 + excess H2O gives an oxyacid and a hydroacid. PCl5 + 1 mole H2O gives an unknown product Z and HCl. The ratio of the number of pi bonds to the number of sigma bonds in compound Z is:

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