Question

In the 1'H NMR spectrum of ethanol at 400 MHz, the methyl group splits into ___number of peaks.

Answer 1

Correct Answer: 3

To determine the number of peaks into which the methyl group of ethanol splits in its ¹H NMR spectrum at 400 MHz, we apply the "n+1" rule. This rule states that a proton (or a group of equivalent protons) will split into n+1 peaks, where n is the number of neighboring protons.

In ethanol (CH₃CH₂OH), the methyl group (CH₃) has two neighboring protons from the methylene group (CH₂). Therefore, we can calculate the splitting of the methyl group using the formula:

Splitting = n + 1, where n = 2.

Thus, Splitting = 2 + 1 = 3.

Therefore, the methyl group in the ¹H NMR spectrum of ethanol splits into 3 peaks.