Which element has 3 valence electrons in the 4dsublevel

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

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Consider this equilibrium: n29) + o2(g) + 2no(c).nitrogen gas and oxygen gas react when placed in a closed container. as the reaction proceeds towards equilibrium, what happens to the rate of thereverse reaction?