Chlorophyll absorbs photons strongly in two bands, one between 340 and 450 nm and the other between 650 and 680 nm. Chlorophyll collects and transfers the photon energy to fix CO2 into carbohydrate CH2O units according to CO2 + H2O → (CH2O) + O2 where the (CH2O) indicates one carbon unit of the carbohydrate. The average enthalpy change for the addition of a carbon unit to a carbohydrate is ΔH = 485 kJ/mol. What is the minimum number of 660 nm photons needed by chlorophyll to add a carbon unit to a carbohydrate? (Remember that there’s no such thing as a partial photon.)

Chlorophyll absorbs photons strongly in two bands, one between 340 and 450 nm and the other between 650 and 680 nm. Chlorophyll collects and transfers the photon energy to fix CO2 into carbohydrate CH2O units according to CO2 + H2O → (CH2O) + O2 where the (CH2O) indicates one carbon unit of the carbohydrate. The average enthalpy change for the addition of a carbon unit to a carbohydrate is ΔH = 485 kJ/mol. What is the minimum number of 660 nm photons needed by chlorophyll to add a carbon unit to a carbohydrate? (Remember that there’s no such thing as a partial photon.)

Chemistry & Chemical Reactivity

9th Edition

ISBN:9781133949640

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter24: Biochemistry

Section: Chapter Questions

Problem 29GQ

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