MDCAT Chemistry MCQ #263

In a diagnostic test to confirm the presence of a carbonyl group, a student adds 2,4-Dinitrophenylhydrazine. What visual evidence confirms a positive result?

MDCAT Chemistry MCQ #263

  1. Question 1

    Q1. In a diagnostic test to confirm the presence of a carbonyl group, a student adds 2,4-Dinitrophenylhydrazine. What visual evidence confirms a positive result?

    • A) Blue precipitate
    • B) Yellow or Orange precipitate
    • C) Silver mirror
    • D) White crystalline solid

    Answer: Yellow or Orange precipitate

    Explanation: Brady's reagent (2,4-DNPH) reacts with the carbonyl group to form yellow or orange precipitates. Blue color is associated with Fehling's reagent, not DNPH.