CSIR (Council of Scientific & Industrial Research) Chemical Sciences: Questions 1 of 862

Appeared in Year: 2014

Question MCQ▾

Fluorescence lifetime of a molecule in a solution is Sum of all non-radioactive rate constant for decay of excited state is 1.2 . The fluorescence quantum yield of molecules is:- (June)

Choices

Choice (4)Response

a.

0.4

b.

0.6

c.

0.2

d.

0.1

Edit

Answer

b.

Explanation

  • Fluorescence:- Light absorbed by a substance may be emitted simultaneously (Radiative transition) emitting light. This is called fluorescence,
  • Quantum yield,

    ________ (1)

    ________ (2)

Image Explaining Jobolanskii Diagram

Here,

)

= 0.6

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