A chemical reaction is at equilibrium when:.a. the reaction occurs quickly. b. there is no reverse reaction possible, only a forward reaction. c. there are equal amounts of products and reactants. d. the rate of the forward reaction equals the rate of the reverse reaction.

D.

Explanation: A chemical reaction is said to be in a state of equilibrium when the rate of the forward reaction equals the rate of the backward reaction, thus, there is no net change in the concentration of reactants and products.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

b is the correct answer

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