The activation energy of each step in a reaction was estimat…

The activation energy of each step in a reaction was estimated using quantum mechanics: Step 1. Cl2 –> 2Cl    Ea = 41 kJ/mol Step 2.   H2S + Cl –> H2SCl    Ea = 67 kJ/mol Step 3.   H2SCl + Cl –> H2SCl2     Ea = 82 kJ/mol Step 4.   H2SCl2 –> 2HCl + S     Ea = 39 kJ/mol What is the slow step?