D. the potential energy of the reactants is low; the potential energy decreases gradually; then increases slightly.
Answer:
There is a basic difference, because mass is the actual amount of material contained in a body and is measured in kg, gm, etc. Whereas weight is the force exerted by the gravity on that object mg. Note that mass is independent of everything but weight is different on the earth, moon, etc.
Manganese alone cannot be a catalyst. However, its oxides can work as a catalyst. Manganes (II, III) oxide has found some applications in certain reactions as a catalyst. These reactions are the oxidation of methane, carbon monoxide, decomposition of NO and the catalytic combustion of organic compounds.