I have no idea how I would determine the answers to these questions. What am I supposed to do?

Question

Based on the properties of the attached functional group, which one of the compounds below would you expect interact most strongly with water, thereby increasing its solubility?
A. CH3-CH2-S-H
B. CH3-CH2-F
C. CH3-CH2-I
D. CH3-CH2-O-H
E. CH3-CH2-Cl
Based on the properties of the attached functional group, which one of the compounds below would you expect interact most strongly with water, thereby increasing it solubility?
A. CH3-CH2-I
B. CH3-CH2-S-H
C. CH3-O-CH3
D. CH3-CH2-NH2
E. CH3-CH2-H

Answer 1

Remember like dissolves like. Water is a polar molecule so the more polar compounds will be more soluble. For example, hexane (completely non-polar) is hardly soluble in water but hexanol is more soluble because of the attached OH group. Looking at the 2nd problem, E is the least solubility because it is non-polar but all of the others have a polar component.