Which mixture will not yield hydrogen gas?
(a) sodium and water
(b) calcium and water
(c) zinc and hydrochloric acid
(d) zinc and concentrated nitric acid
(e) steam and red hot iron

The activation energy for the reaction no2(g)+co2(g)⟶no(g)+co(g) is ea = 300 kj/mol and the change in enthalpy for the reaction is δh = -100 kj/mol . what is the activation energy for the reverse reaction?

Athe top of a hill, an athlete on a skateboard has x joules of mechanical energy. how much mechanical energy will she have at the bottom of the hill? ignore the effects of friction.

The most common form of matter in the universe