A white precipitaion forms. Effective concentration are increased So collision frequency is increased. Slight increase in collision frequency occurs. More molecules have enough energy that many more collisions have the necessary activation energy. Raises reaction rate a great deal.
Catalytic nickel lowers the activation eneryg needed for a reaction.
More often molecules have the needed energy for a reaction. More catalytic sites means a greater rate. Measure the amount of C-14 in the dead wood. Compare with the amount of C-14 in a similar living object.