how many grams of KNO3 will precipitate out if 50 grams are dissolve it 100 grams of water at 70⁰C and then cooled to 20⁰ C?

Which factor is likely to impact the possible number of compounds? presence of unlimited number of elements in the periodic table the inability of atoms to align perfectly with other atoms the ability of all elements to react with every other element all elements being equally reactive