Question

Which of the following statements about water is FALSE? Water carries a dipole because of the geometry of the two oxygen-hydrogen bonds.
a. Substances with polar functional groups are generally soluble in water.
b. The hydrophobic effect is driven largely by the entropy of the non-polar substance.
c. A network of electrostatic interactions exists between the molecules in water.
d. Water will act as a hydrogen bond acceptor with hydroxyl groups.

Answer 1

Answer:

b. The hydrophobic effect is driven largely by the entropy of the non-polar substance.

Explanation:

The hydrophobic effect is the tendency of nonpolar substances to aggregate when placed in a watery medium. Water has a tendency to form a maximum number of hydrogen bonds with other water molecules or polar substances. When the nonpolar substances are present in water, the water molecule is not able to form the optimum number of hydrogen bonds.

The nonpolar substance orient themselves around the water molecule to allow the formation of hydrogen bonds. This orientation is energetically unfavorable as water molecules are present in a more organized pattern and have lesser entropy that the bulk water. This results in a hydrophobic effect wherein the nonpolar substances exclude water to increase the entropy of water.