34. given the fact that the concentrations of reactants and
products are not changing, why is the word dynamic
used to describe chemical equilibrium?

The word dynamic is used to describe chemical equilibrium because even though the concentration of reactants and products remains constant, the reaction does not stop, but still continues with the rate of forward reaction equal to the rate of backward reaction. This is opposed to static equilibrium where there is no reaction at all.

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c- cold periods in earth's history during which glaciers covered much of the surface.

explanation:

1 a

2 d

3 a

4 c

explanation: