How do the isotopes hydrogen-1 and hydrogen-2 differ?

At 300 mm hg, a gas has a volume of 380 l, what is the volume at standard pressure

In apex! a liquid heated beyond a certain temperature becomes

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?