Question

1.Calculate the frequency of a chemical shift at 1.25 ppm using a 400 MHz NMR spectrometer.A)1500 HzB)450 HzC)320 HzD)500 Hz

Answer 1

Answer:

D

Explanation:

Chemical shift is given as

Frequency/frequency of instrument

Let c = chemical shift

F = frequency

I = frequency of instrument

Chemical shift = frequency/frequency Instrument

1.25ppm = Frequency /400

We cross multiply to find frequency

Frequency = 400 x 1.25

Frequency = 500Hz

Option d is the answer since it is 500hz