Which of the following processes are spontaneous? (a) A satellite falls to Earth. (b) Water decomposes to H2 and O2 at 298 K and 1 atm. (c) Average car prices increase.

Hydrogenation reactions, in which h2 and an "unsaturated" organic compound combine, are used in the food, fuel, and polymer industries. in the simplest case, ethene (c2h4) and h2 form ethane (c2h6). if 140 kj is given off per mole of c2h4 reacting, how much heat (in mj) is released when 12 kg of c2h6 forms?