In order for a solute to dissolve in a solvent, what must be true?

Consider the following reactions. (note: (s) = solid, (l) = liquid, and (g) = gas.) mg(s) + ½o2(g) → mgo(s) + 146 kcal/mole h2(g) + ½o2(g) → h2o(g), δh = -57.82 kcal/mole what type of reaction is represented by the previous two examples?

Which type of precipitation would most likely form when the surface air temperature is slightly below freezing and the air temperature increases as you move upward away from the ground?

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17