Suppose that you want to prepare 2.00*10^3 L of ammonia gas, NH3 , from the reaction of hydrogen gas with nitrogen gas. What volume of hydrogen and nitrogen do you need? Assume that the temperature and pressure remain constant during the reaction. 3H2(g) + N2(g) -> 2 NH3(g) V H2 = 2.00*10^3 L NH3 * (3 vol H2 / 2 vol NH3) = 3.00*10^3 L H2 V N2 = 2.00*10^3 L NH3 * (1 vol N2 / 2 vol NH3) = 1.00*10^3 L N2 Therefore, 3.00*10^3 L of hydrogen and 1.00*10^3 L of nitrogen is required to make 2.00*10^3 L of ammonia. This is an example in my text book. My question is: how is it that when 3000L of hydrogen and 1000L of nitrogen are combined it produces only 2000L of ammonia? Is the question stated incorrectly, is it taking into account only one volume of ammonia produced, or does the chemical reaction between hydrogen and nitrogen produce a more closely condensed ammonia gas?