Select all that apply. when the products of a reaction have more energy than the reactants: the reaction is exothermic. the reaction is endothermic. the reactants gave up energy. the δh is positive.

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?

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?

How many neutrons does an element have if its atomic number is 50 and its mass number is 166