Which one of these elements was suggested as transition element by Mendeleev?
(a) N
(b)Ni
(c)Ne
(d)none

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For each of the following types of reactions, write a general reaction formula in the symbolic form—for example, a + b → ab. single-displacement double-displacement synthesis decomposition

Which statement is true about a catalyst? a: a catalyst decreases the rate of the reaction. b. a catalyst is consumed during a chemical reaction. c. a catalyst lowers the activation energy of a reaction. d. a catalyst increases the reactant concentration during a reaction.