6. Gas reaction stoichiometry - combining volumes What is the final volume if 20 L methane reacts completely with 20 L oxygen CH_(4)(g)+2O_(2)(g)arrow CO_(2)(g)+2H_(2)O(l) At 100^circ C and 2 atmospheres a) 15L b) 10L C 20L d) 30L

To solve this problem, we need to use the concept of combining volumes in gas reactions.<br /><br />Given information:<br />- 20 L of methane (CH4) reacts completely with 20 L of oxygen (O2).<br />- The balanced chemical equation is: CH4(g) + 2O2(g) → CO2(g) + 2H2O(l).<br />- The temperature is 100°C and the pressure is 2 atmospheres.<br /><br />According to the balanced chemical equation, 1 volume of methane reacts with 2 volumes of oxygen to produce 1 volume of carbon dioxide.<br /><br />Since the volumes of methane and oxygen are both 20 L, the methane will be completely consumed, and the oxygen will be in excess.<br /><br />The final volume of the reaction mixture will be equal to the volume of the limiting reactant, which is the methane in this case.<br /><br />Therefore, the final volume is 20 L.<br /><br />The correct answer is:<br />c) 20 L