Answer:
Based on the data provided in the table, we can analyze and answer the questions as follows:
Classify each fatty acid as saturated or unsaturated:
Lauric acid (C12H24O2) has 0 double bonds, making it a saturated fatty acid.
Palmitoleic acid (C16H30O2) has 1 double bond, making it an unsaturated fatty acid.
Linoleic acid (C18H32O2) has 2 double bonds, making it an unsaturated fatty acid.
Interpret the effect of the increase in the number of double bonds on melting point:
Lauric acid, being a saturated fatty acid with no double bonds, has the highest melting point at 45°C.
Palmitoleic acid, with 1 double bond, has a significantly lower melting point at 0.5°C compared to lauric acid.
Linoleic acid, with 2 double bonds, has an even lower melting point at -5°C compared to the other two fatty acids.
The trend here is that as the number of double bonds increases, the melting point of the fatty acid decreases. Unsaturated fatty acids with double bonds have lower melting points compared to saturated fatty acids with no double bonds. This is because the double bonds introduce kinks in the fatty acid chains, making them less able to pack closely together, which reduces the strength of intermolecular forces, such as van der Waals forces. As a result, less thermal energy is required to break these weaker forces and melt the substance.
Identify whether each fatty acid is solid or liquid at room temperature (25°C):
Lauric acid is a saturated fatty acid with a melting point of 45°C, so it is a solid at room temperature (25°C).
Palmitoleic acid, an unsaturated fatty acid with a melting point of 0.5°C, is a liquid at room temperature (25°C).
Linoleic acid, another unsaturated fatty acid with a melting point of -5°C, is also a liquid at room temperature (25°C).
In summary, saturated fatty acids tend to be solid at room temperature due to their higher melting points, while unsaturated fatty acids tend to be liquid at room temperature due to their lower melting points, which are influenced by the presence of double bonds.
Step-by-step explanation: