For each event, indicate how the concentration of each species in the chemical equation will then change to reach equilibrium. An up arrow indicates an increase in concentration, a down arrow indicates a decrease in concentration, and leaving it blank means there is no change in the concentration. 2 CO ( g ) + O 2 ( g ) − ⇀ ↽ − 2 CO 2 ( g ) increasing the concentration of CO increasing the concentration of CO 2 decreasing the volume of the system