Simple Colloid Mixture Examples in Chemistry

You create mixtures when you combine two or more substances. These substances include particles and dispersion mediums, usually in different states of matter. When the particles and mediums are insoluble but do not separate from each other, you have created a colloid mixture.

A colloid mixture consists of the following properties:

• The particles in the mixture are between 1 and 1000 nanometers in diameter.
• The particles cannot be filtered out of the mixture, but they do not separate from the dispersing medium.
• The mixture is heterogeneous.
• Light scatters when it is shone through some colloidal mixtures because of the Tyndall effect. The colloidal particles block the light, but the dispersion medium doesn’t.

Combining different substances can result in five main types of colloid mixtures: aerosols, foams, emulsions, sols and gels.

Some of these colloids exist naturally in the world, while others are man-made products. Depending on the types of particles and dispersion mediums you use, colloid mixtures can be healthy, neutral, or dangerous.

When you add liquid particles to a gas medium, you create an aerosol. Solid aerosols occur when solid particles combine with a gas medium. Air is usually the gas medium involved in this colloid mixture.

Examples of aerosols:

• Hairspray
• Perfume
• Mist
• Fog

Examples of solid aerosols:

• Smoke
• Smog
• Dust
• Volcanic ash

You can create a foam when you add gas particles to a liquid medium. Firmer foams, known as solid foams, are formed when gas particles combine with a solid medium.

Examples of foams:

• Whipped cream
• Bubble bath
• Fire retardant

Examples of solid foams:

• Insulation foam
• Yoga mats
• Memory foam

Emulsions are colloids in which liquid particles combine with a liquid medium. These substances don’t mix perfectly; otherwise, they wouldn’t be colloids. However, the combinations made from liquids with different properties result in many household foods.

Examples of emulsions:

• Mayonnaise
• Milk
• Salad dressing
• Brewed coffee

Sol mixtures combine solid particles with a liquid medium. Sols are the most common type of colloid that you’ll find. Solid sols, which have solid particles mixed with a solid medium, are not as common.

Examples of sols:

• Blood
• Ink
• Paint
• Mud

Examples of solid sols:

• Glass
• Colored glass
• Gemstones

Gels add liquid particles to solid mediums. Their mixtures can be similar to sols, but the structure of a gel is more solid and jelly-like than a sol. If you heat a gel, it will become a sol. Conversely, if you cool a sol, it can become a gel.

Examples of gels:

• Toothpaste
• Jam
• Cheese
• Rubber
• Gelatin

Colloids are only one type of mixture. However, all mixtures are made of two parts: particles and the dispersing medium. Two other types of mixtures are solutions and suspensions.

Solutions are mixtures in which the particles are completely soluble with the dispersion medium. You can tell if you have a solution mixture when:

• The particles in the mixture are smaller than 1 nanometer in diameter.
• The particles are uniform throughout the mixture, making the mixture homogeneous.
• The particles cannot be filtered out.
• Light passes through the mixture easily.

Suspension mixtures have particles that float to the top or sink to the bottom of the container.

• The particles in the mixture are larger than 1000 nanometers in diameter.
• Particles can be filtered out of the mixture and separate from the standing dispersing medium.
• Like colloid mixtures, suspension mixtures are heterogeneous.
• Light either scatters or is completely blocked when passing through a suspension mixture.

The difference between colloid and suspension mixtures is simple. If you can see the particles in a mixture or they settle to the bottom of a container, you’re looking at a suspension mixture. If the mixture consists of two states of matter in a stable suspension, you have a colloid. Solutions are blended so well that they only consist of one state of matter.

If you’ve got more mixtures in mind, we've got more resources for you. Check out these examples of saturated solutions if you’d like to learn more about the different types of mixtures. You can also review a list of chemical properties to ensure that your science reports are detailed and accurate.