AICE Chemistry Practice Exam

The reagent that is commonly used for the elimination of halogenoalkanes to produce alkenes is sodium hydroxide (NaOH). In the elimination reaction, NaOH acts as a strong base that facilitates the removal of a halogen atom (such as chlorine or bromine) and a hydrogen atom from adjacent carbons in a halogenoalkane. This process results in the formation of a double bond, yielding an alkene.

The mechanism typically follows an E2 pathway, especially when a strong base like NaOH is used, leading to the concerted removal of the halide and a hydrogen atom, resulting in the formation of the double bond. This reaction is favored in conditions where high temperature is applied, which further promotes elimination over substitution reactions.

Other reagents listed have different functions:

- Hydrochloric acid (HCl) is more likely to promote substitution reactions rather than elimination.

- Potassium permanganate (KMnO4) is primarily used as an oxidizing agent and does not facilitate elimination to form alkenes.

- Dichromate (K2Cr2O7) is also an oxidizing agent used in various oxidation reactions, not for the elimination process.

Thus, NaOH effectively facilitates the