When you put cooking oil in water, they do not mix; instead, they form two distinct layers.
Why Oil and Water Don't Mix
The primary reason oil and water don't mix comes down to the behavior of their molecules. According to the reference, the water molecules attract each other, forming strong bonds between themselves. Similarly, the oil molecules stick together, although their attraction is different from water's.
This difference in attraction causes the two substances to essentially 'prefer' staying with their own kind rather than mixing with the other.
The Result: Separate Layers
Because the water molecules attract each other and the oil molecules stick together, that causes oil and water to form two separate layers when combined. They are considered immiscible, meaning they cannot dissolve into one another.
Why Oil Floats on Water
Not only do they form layers, but the layers also arrange themselves vertically. Water molecules pack closer together, making water denser than cooking oil. Because water is denser, they sink to the bottom, leaving oil sitting on top of the water. This is why you typically see oil floating on the surface when added to water.
Key points:
- Water molecules attract each other.
- Oil molecules stick together.
- This leads to the formation of two separate layers.
- Water is denser and sinks.
- Oil is less dense and floats on top.
This phenomenon is a classic example of how substances with different molecular properties behave when combined.
