Question

(a) P700 in its ground state has reduction potential +0.5V. Excitation of P700 by light decreases

the reduction potential to –1.2 V. Calculate ΔG o' in kJ/mol for this shift in reduction potential.

(b) How efficient is this process compared to an einstein (mole of photons) of wavelength 700 nm?

(c) How efficient is this process compared to an einstein (mole of photons) of wavelength 435 nm?

(d) Compare the results in (b) and (c) and explain why they differ.

(e) What is the maximum wavelength of light that can drive this change in redox potential in P700?

Answer 1