Which of the following molecules has the most acidic hydrogen atoms?

Question

Quizplus · Accepted Answer

The most acidic hydrogen atoms are those that are attached to electronegative elements. In molecule I, there are no hydrogen atoms attached to electronegative atoms. In molecule II, the hydrogen atom attached to the oxygen atom is acidic, but in molecule III, both hydrogen atoms attached to the nitrogen atoms are more acidic due to the greater electronegativity of nitrogen compared to oxygen. In molecule IV, the hydrogen atom attached to the sulfur atom is less acidic than those in molecule III due to the larger size of sulfur compared to nitrogen, which reduces the acidity of the molecule. Therefore, molecule III has the most acidic hydrogen atoms.

Which of the Following Molecules Has the Most Acidic Hydrogen