Why does an oil-and-vinegar salad dressing have two separate layers?

Answer 1

This is because water and oil do not mix. Oil is hydrophobic meaning does not mix with water while water is clearly hydrophilic as it mixes with other water molecules. Most Oils is lighter then water so the oil goes to the top.

Answer 2

Oil and vinegar have different molecular properties that cause them to repel each other rather than mix together. The oil is less dense and floats on top of the vinegar, creating the distinct layers in the salad dressing. Mixing or shaking the dressing helps temporarily emulsify the two liquids, but they eventually separate again due to their natural properties.

Answer 3

Oil and vinegar separate into layers in a bottle of salad dressing because vinegar is more dense than oil, and therefore goes to the bottom. The less dense vingear stays ontop.

Answer 4

Oil and vinegar separate into layers in a bottle of salad dressing because vinegar is more dense than oil, and therefore goes to the bottom. The less dense vinegar stays on top.