Question

Butter is a solid at room temp because it is made up mostly of ___ fatty acids, whereas oil is a liquid at room temperature because it is made up mostly of ___ fatty acids.

1) unsaturated, saturated
2) polyunsaturated, monounsaturated
3) saturated, unsaturated
4) unsaturated, polyunsaturated

Answer 1

Butter is solid because it contains saturated fatty acids which pack tightly together, while oils are liquid due to unsaturated fatty acids with kinked structures that cannot pack as closely.

Step-by-step explanation:

Butter is a solid at room temperature because it is made up mostly of saturated fatty acids, whereas oil is a liquid at room temperature because it is made up mostly of unsaturated fatty acids. The correct answer to the question is option 3) saturated, unsaturated.

Saturated fatty acids are straight, rigid chains that pack tightly together due to the lack of double bonds in their molecular structure. This close packing makes substances like butter solid at room temperature. In contrast, unsaturated fatty acids, which include monounsaturated and polyunsaturated fats, have one or more double bonds that introduce kinks in their structure, preventing tight packing and resulting in a liquid state at room temperature, as seen in vegetable oils like olive and canola oil.