Is warm water or cold water more dense

Which statement describes both homogeneous mixtures and heterogeneous mixtures?

What term is missing from the central region that describes hypotheses, theories, and laws? popular predictable mathematical falsifiable

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?