How can a rock form by evaporation? what type of rock is it

Crystsals can precipitate out of solution when some of the solvent is evaporated. For example, if you have sodium chloride in solution and you evaporate out the water some sodium chloride crystals will form. I hope this helps. Let me know if anything is unclear.

Because electrons have negligible mass, to account for the mass of the isotope, there must be 16 neutrons, 16 neutrally charged, massive, fundamental particles present in the sulfur nucleus. and thus finally, if we have the 32s2− ion, there are 18 electrons, 16 protons, and 16 neutrons.