Question

HNCO (isocyanic acid) has following resonating structures :

$\longleftrightarrow$$\longleftrightarrow$

The order of stablityis :

• A. I > III > II
• B. I > II > III
• C. II > III > I
• D. II > I > III

Answer 1

Answer: (A)

I > III > II

Answer 2

> $\mathrm { H } - \stackrel { \oplus } { \mathrm { N } } \equiv \mathrm { C } - \mathrm { O } ^ { \ominus }$ III (-ve charge is more stable on high E.N. atom) >