why is the sionifcan Stractuxes How ie mey related to cbesg

why is the sionifcan Stractuxes ?How ie mey related to cbesg ifrcance of draiwing fesonance ergh

Solution

Resonance structures are used to describe delocalization of electrons within certain molecules where the bonding cannot be expressed by one single Lewis structure. The resonance structures are also known as contributing structures or canonical structures. Resonance structures of a molecule differ in the arrangements of electrons.

Lower potential energy of a contributing structure of a molecule indicates that it is more stable. The real structure of a molecule has a lower total potential energy than each of the contributing structures would have. Drawing resonance structures help us to identify stable contributing structures among all possible resonance structures.

It is important to know that any molecule or ion exists in only one form – the resonance hybrid. The resonance hybrid is the approximate intermediate of stable contributing structures, and the overall energy is lower than each of the contributors, due to the resonance energy. In other words, structures with a low value of potential energy are more stable than those with high values and resemble the actual structure more.

The greater the number of contributing structures, the more stable the molecule. This is because the electrons in a particular molecule have more states at lower energy available. Also the more volume electrons can occupy at lower energy the more stable the molecule is.

Examples:

S=C=N^- <-> ^-S-CN

^-O-C(R)=O <-> O=C(R)-O^-