UPSC Civil Services (Mains), Chemistry optional · 2021 · Paper I
Q5(b). Lambert–Beer law: statement and derivation
Question
State and derive Lambert-Beer law for absorption of light by solutions.
Answer in brief
A = log₁₀(I₀/I) = εcℓ, or I = I₀10−εcℓ: absorbance is proportional to the concentration and to the path length.
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CoversBeer–Lambert lawabsorbancemolar absorption coefficienttransmittancespectrophotometry
All parts of Question 5
- 5(a) Rate constant and half-life of a zero-order reaction10 marks
- 5(b) Lambert–Beer law: statement and derivation10 marks
- 5(c) Oxidation of haem to hematin, and how the protein prevents it10 marks
- 5(d) Geometrical isomers and stereoisomers of M(AB)b₂c₂10 marks
- 5(e) Completing five reactions of xenon compounds10 marks