Saturated fat molecule or unsaturated fat molecule

Molecule A

Molecule B

Based on the structure for both fat molecules,

1. Which molecule is a unsaturated fat molecule? Why?
2. Which homologous series does molecule A belong to? Why?
3. State two difference of both molecules.
4. Which molecule can undergo catalytic hydrogenation? State the condition of the reaction.

Relationship Between Homologous Series

Name the reaction P, Q, R, S, T and U.