Hydrogen gas and chlorine gas react according to the following equation h2(g) + cl2(g) < > 2hcl(g) + energy hydrogen gas and chlorine gas are placed in a sealed container and are allowed to reach equilibrium. what effect will heating the system have?

H2(g) + Cl2(g) <> 2HCl(g) + Energy

Because this reaction is going with release of heat, so adding more heat  will shift this reaction toward the side that is going to remove this heat, to the reactant side.

H2(g) + Cl2(g) <> 2HCl(g) + Energy
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The reaction will shift to the right