Consider the reaction in which HCl adds across the double bond of ethene: HCl + H2C=CH2- H3C-CH₂CI The following mechanism, with the accompanying energy dia- gram, has been suggested for this reaction: Step 1 HCI H2C=CH2 Step 2 H3C CH₂+ + CI Ea TAH C=C + HCl H3C CH₂+ Cl¯ H3C-CH₂CI -Eaz H-C-C-Cl -Reaction progress- a. Based on the energy diagram, determine which step is rate limiting. b. What is the expected order of the reaction based on the pro- posed mechanism? c. Is the overall reaction exothermic or endothermic?​