Q.Describe the splitting of water (photolysis) at Photosystem II, naming the complex that catalyses it, and state its three products and their respective fates.

[!TLDR]

Water splitting at PS II's water-splitting complex releases electrons (to PS II), protons (to the lumen, for ATP synthesis) and O2 (released to the atmosphere). …

PS II's photoactivated, oxidised reaction centre (P680+) is a powerful enough oxidant to split water at the manganese-containing water-splitting (oxygen-evolving) complex on the lumenal side of the thylakoid membrane: 2H₂O → 4H⁺ + O₂ + 4e⁻. The electrons released refill the electron hole in PS II, allowing it to be reused for further photoactivation events; the protons are released directly into the thylakoid lumen, adding to the trans-thylakoid H+ gradient that drives ATP synthesis via chemiosmosis; and the O2 released diffuses out of the chloroplast and the leaf, constitutin …

List the three products of water splitting one by one and give each …

Forgetting that all three products (electrons, protons, O2) have distinct downstream roles -- listing only O2 release misse …