Photosynthesis

Evil

hi ppl, i have some questions here about photosynthesis,really appreciate if you can answer them for me.
1) If a chlorophyll solution is excited with UV radiation, how do we know what colour is the fluorescence?
2)In the water splitting step of photosynthesis, two Hydrogen ions and one oxygen atom are formed. Whats to prevent them from forming water again or to react with other substances in the stroma?
3)Whatz the difference between ATP and NADPH , both structually and function wise.

thanks for your input. really appreciate it.