Which of these is a conversion from chemical energy to mechanical energy?

A. A dark light bulb starting to glow

B. A ball rolling down a hill

C. A person lifting a weight

D. A potato being heated in an oven

adding or remove a gaseous reactant or product changes the concentrations. if the concentration of reactant or product is increased, the system will shift away from the side in which concentration was increased (i.e. if the concentration of reactants is increased, the system will shift toward the products. if more products are added, the system will shift to form more reactants). conversely, if the concentration of reactant or product is decreased, the system will shift toward the side in which concentration was decreased (i.e. if reactants are removed, the system will shift to form more reactants. if the concentration of products is decreased, the equilibrium will shift toward the products).

explanation:

it's c. elements are placed in rows based on how may valencies electrons have.