Answer:
1 and 2
Explanation:
When Concentrated H2SO4 reacted with the alcohols, they produce cycloalkenes. This is a mechanism known as dehydration of alcohols with an acid catalyst. This is because concentrated H2SO4 acts as a great oxidizing agent. In the process, the alcohols are heated to a high temperature with an excess of pure sulfuric acid. By passing the gases through a sodium hydroxide solution, the carbon dioxide and sulfur dioxide produced by reactive species are eliminated. The reaction mechanism shown in the image below indicates that only compounds 1 and 2 produce only one product.
