Q91 · CSIR-NET Chemistry, June 2015

Paper: CSIR-NET June 2015 · Subject: Physical Chemistry · Chapter: Molecular Spectroscopy · Topic: Rotational · Marks: 2 · Difficulty: Medium

The spectroscopic technique, by which the ground state dissociation energies of diatomic molecules can be estimated, is
(a)Microwave spectroscopy
(b)Infrared spectroscopy
(c)UV-visible absorption spectroscopy
(d)X-ray spectroscopy
Answer
Answer: C ✓ checked by 4AB · confidence high

The source book printed B; on checking, C is correct — see the explanation.

Printed B; IR gives only the first few levels, the electronic spectrum reaches the dissociation limit.

Explanation
The vibrational progression of an electronic (UV–visible) band converges to the dissociation limit; Birge–Sponer extrapolation of it gives D₀ of the ground state.

Study loop for Molecular Spectroscopy

1. Practise the PYQsPrevious-year questions, with answers

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