What is the energy in electron-volts (ev) of a photon of green light that has a wavelength of 520 nm? (1.0 m = 1.0 × 10^-9m)

3.8 × 10^-19ev
3.4 × 10^-40ev
2.4ev
2.2 × 10^-21ev

The density of a liquid could be found by using

The electronic structure or chlorine is 2.8.7 what is the electronic structure of fluorine?

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !