Why do the oceans play such a large part in the water cycle

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?

Consider the story you just read. all but one of the choices below indicate that something is living.

The empirical formula of a compound is ch2o and its mass is 120 amu/molecule, what is its formula?