Which of the following mixtures does not form an azeotrope at atmosheric pressure?

ANS:D - None of these

"None of these" means that none of the mixtures listed in the options form an azeotrope at atmospheric pressure. Let's briefly discuss each mixture:

1. Water-alcohol: This mixture can indeed form azeotropes, depending on the specific alcohol involved and its concentration. For example, ethanol-water mixtures form several azeotropes at different concentrations and temperatures.
2. Methyl alcohol-acetone: Methyl alcohol (methanol) and acetone do not form an azeotrope at atmospheric pressure. They have different boiling points and compositions, so they do not exhibit the phenomenon of azeotropy under normal atmospheric conditions.
3. Butyl acetate-water: Similarly, butyl acetate and water do not form an azeotrope at atmospheric pressure. Although mixtures of these substances may exhibit some degree of mutual solubility and boiling point elevation, they do not form constant boiling mixtures with fixed compositions like azeotropes.