200 ml of KOH and 200 ml of HNO3 of same molarity are mixed together and liberated 3.426 kJ of heat. Determine the molarity of each solution.

 

Consider the chemical reaction at 300 K H2 (g) + Cl2 --> HCl(g) ΔH= -185KJ/mole calculate ΔU if 3 mole of H2 completely react with 3 mole of Cl2 (g) to form HCl.

 

                           H₂ (g)+Cl_{2 -->}  HCl(g) ΔH= -185KJ/mole

                                       Δng=0

                                   ΔH= ΔU+ ΔngRT

                                  ΔH= ΔU

                       ΔH_R= -185 KJ/mole ,ΔU_R= -185 KJ/mole

                       H₂ (g)+Cl_{2 -->} HCl(g) ΔH= -185KJ/mole

                         3 mole       3 mole

            Hence           ΔU= -185 X 3 KJ/Mole