(1) In 1791, French doctor Lou Blanc was the first to obtain a patent for making alkali. He used salt, concentrated sulfuric acid, limestone, and coal as raw materials to make alkali. The method was d

(1) In 1791, French doctor Lou Blanc was the first to obtain a patent for making alkali. He used salt, concentrated sulfuric acid, limestone, and coal as raw materials to make alkali. The method was divided into three steps: ①

B

According to the fact that the redox reaction is a reaction with changes in valence, step 2 is a redox reaction, so A is wrong and B is right; HCl is produced in this production, which is harmful to the production. The equipment is severely acid-corroded; the CO generated in step 2 is an atmospheric pollutant, so C and D are wrong.