Answer:propanoic acid
Explanation:
Carboxylic acids contain the COOH group. This group is capable of hydrogen bonding leading to association of the molecules. Cyclobutane is a cyclic alkane and acetone is a ketone. Non of these compounds posses a polar -OH bond which is necessary for the occurrence of hydrogen bond. Hydrogen bonds only occur in carboxylic acids and alcohols. Hydrogen bond leads to molecular association and high boiling points.
Litmus solution is generally a purple dye. The solution of Litmus is extracted from lichens. The Litmus solution is used as an indicator to determine the acidic and basic nature of a solution.Lichens plants belonging to the class of Thallophyta. The litmus solution method involves the grinding and crushing of lichens. In order to get the desired litmus solution, such dyes are then introduced to neutral water.