Adding a catalyst to a system at equilibrium lowers the activation energy required by a system, which shifts the equilibrium position toward the products

A catalyst speeds up a reaction by lowering the activation energy.

Explanation:

A catalyst has no effect on the equilibrium of a reaction.A catalyst does not add energy to a reaction neither does a catalyst consumed in a chemical reaction .

Therefore, A catalyst speeds up a reaction by lowering the activation energy.

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.