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ChemistryEasyMCQ2022 · 24 Jun Shift 2

Q32.The energy of one mole of photons of radiation of wavelength 300 nm is (Given : h = 6. 63 × 10−34 J s, NA = 6. 02 × 1023 mol−1c = 3 × 108 m s−1 ) (1) 235 kJ mol−1 (2) 325 kJ mol−1 (3) 399 kJ mol−1 (4) 435 kJ mol−1

What This Question Tests

This question is a direct application of the formula for the energy of a photon and its conversion to molar energy using Avogadro's number.

Concepts Tested

Energy of a photonPlanck's constantAvogadro's numberWavelength-frequency-energy relation

Formulas Used

E = hc/λ

Energy per mole = N_A * E

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