A student sets up two reactions. Reaction 1 uses 0.210 mol/L of reactant, and Reaction 2 uses 0.530 mol/L of reactant. How many times faster is Reaction 2 compared to Reaction 1?
Express your answer as a multiple of the rate for Reaction 1 to three significant figures. Note that Reaction 1 is already written for you, so just enter the number.