Complex sentence: The second row, labelled C for Change, specifies that when the acid dissociates, its concentration changes by an amount "-x" and the concentrations of A-and H + both change by an amount "+ x".
Split into simpler sentences: The second row, labelled C for Change, specifies the changes that occur when the acid dissociates. The acid concentration decreases by an amount "-x" and the concentrations of A-and H + both increase by an amount "+ x".