About how long does it take for the reaction to reach equilibrium in this concentration versus time graph? a graph of reactant and product concentration vs. time; a red curve shows the reactant concentration decreasing while two blue curves show the product concentration increasing with time; both blue curves intersect the red curve; the chemical equation is water reacting to produce hydrogen and oxygen A. 0.5 second B. 1.5 seconds C. 2.5 seconds D. 4.5 seconds