Page 99 - Practical-organic-3

❖ Choose the correct answer:

1. Mass spectrometer separates ions on the basis of which of the following?

a) Mass.

b) Charge.

c) Molecular weight.

d) Mass to charge ratio.

2. Which of the following corresponds to the molecular ion in a mass spectrum?

a) Any ion formed by fragmentation of the molecule.

b) The ion with the smallest m/z.

c) The most abundant ion.

d) The ion formed by removal of an electron from the molecule.

3. Which of the following is the definition of the base peak in a mass spectrum?

a) The peak corresponding to the ion with lowest m/z.

b) The peak corresponding to the molecular ion.

c) The peak corresponding to the most abundant ion.

d) The peak corresponding to any ion formed by fragmentation of the molecule.

❖ Write the m/z of required fragments in the following MS spectrum:

Required +1

fragments Molecular ion M Base peak

m/z

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