Question

what is n+1 rule and give example

Answer 1

The (n+1) Rule, an empirical rule used to predict the multiplicity and, in conjunction with Pascal's triangle, splitting pattern of peaks in 1H and 13C NMR spectra, states that if a given nucleus is coupled (see spin coupling) to n number of nuclei that are equivalent (see equivalent ligands),

Answer 2

n+1 rule is an empirical rule that is used to predict multiplicity in conjugation with Pascal's triangle.

• When we observe the NMR spectra of the splitting patterns of peaks of  H¹, we can conclude that if the nucleus is coupled to the 'n' number of nuclei that are equivalent then the multiplicity of the peak is n+1.

• Example: In CH₃Cl or methyl chloride, the molecule contains one carbon atom attached to 3 hydrogen atoms and 1 chlorine atom.

• The three hydrogen atom present in CH₃Cl are said to be equivalent because the three hydrogen nuclei = 1