MDCAT Chemistry MCQ #674

A technician uses magnesium turnings in dry ether to prepare a Grignard reagent. Why is the presence of moisture strictly avoided during this synthesis?

MDCAT Chemistry MCQ #674

  1. Question 1

    Q1. A technician uses magnesium turnings in dry ether to prepare a Grignard reagent. Why is the presence of moisture strictly avoided during this synthesis?

    • A) Magnesium reacts with water to form MgO
    • B) Ether becomes explosive with water
    • C) The Grignard reagent reacts to form an alkane
    • D) The alkyl halide hydrolyzes to an alcohol

    Answer: The Grignard reagent reacts to form an alkane

    Explanation: Grignard reagents are highly reactive bases and react with water to form alkanes. Hydrogen gas is tempting but the alkyl group protonates.