Liquids that refuse to mix
Immiscible liquids form layers.
Oil in water
Oil falls into a container of water. A cup of acetone is poured into another cup of water.
What do you expect?
What this lesson covers
The idea
Liquids that fail to mix and instead form separate layers are called immiscible liquids; together they form a heterogeneous mixture.
Oil in water
Oil falls into a container of water. A cup of acetone is poured into another cup of water.
What do you expect?
- The oil stays apart in a layer, but acetone mixes with water
- Both mix completely
- Neither mixes
Shake and wait
Two jars have just been shaken. Let time pass. Which one stays mixed?
Immiscible liquids
Liquids that do not mix and instead form separate layers are called immiscible liquids. Together they form a heterogeneous mixture. Liquids that mix completely are miscible.
Oil and water are immiscible. Sand and water, and iron filings and sulfur, also do not mix and are heterogeneous mixtures.
A separating funnel separates two immiscible liquids by using their different densities.
Notes
Immiscible liquids do not mix: they form separate layers and a heterogeneous mixture.
Check yourself
Oil and water do not mix and form two layers. We call them…
Oil and water form separate layers. What kind of mixture is this?
Which pair is miscible?
What is used to separate two immiscible liquids?
- miscible liquids. Miscible liquids mix completely.
- immiscible liquids — correct. Yes.
- a solution. A solution is uniform; this is not.
- Heterogeneous — correct. Yes. It is not uniform.
- Homogeneous. A homogeneous mixture is uniform.
- A single pure liquid. It is two liquids.
- Oil and water. They form separate layers.
- Sand and water. Sand does not mix with water; it settles.
- Acetone and water — correct. Yes. They mix completely.
- A magnet. A magnet picks up magnetic solids.
- A separating funnel, using their different densities — correct. Yes.
- A condenser. That cools vapour in distillation.