There’s more to a mixture than meets the eye. Empower your teen to learn more about the world of mixtures by making their own DIY lip balm. You can find out exactly how in my freebie, Empower Your Teen’s Creativity: Hands on Science Activities for Learning and Fun.
The lip balm is made from a combination of beeswax, coconut oil, shea butter, and essential oils. These ingredients form an emulsion, which is a type of mixture. You’ll learn all about that below!
What is a Mixture
A mixture is a combination of two or more substances in which each substance retains its own chemical properties. The components are physically combined but not chemically bonded and can be separated.
All the states of matter (liquid, solid, and gas) can combine to form mixtures.
Let's take a look at trail mix for example, which is a combination of various snacks. Even though all the snacks have been mixed together, they still each have their own individual properties.
There are two types of mixtures:
Homogeneous: The components of the mixture are evenly distributed. The mixture is uniform throughout, the components are evenly distributed and you cannot separate them easily. An example is air which is a mixture of gasses or tea with sugar dissolved in it.
Heterogeneous: The components of the mixture are not evenly distributed. Each component has visually distinguishable properties and you can often see or separate them easily. Like in your trail mix, you can see each individual snack and separate them into different categories if you wanted to. Another example is a mixture of sand and water.
There are a few different categories of mixtures. They will be explained below.
Solution
A solution is a homogeneous mixture where one substance (the solute) is uniformly dispersed in another substance (the solvent). In a solution, the particles of the solute are so small that they dissolve and become indistinguishable from the particles of the solvent.
Solutions can be in various states: gas (like air), liquid (like saltwater), or solid (like brass).
Characteristics:
The solute particles are very small and do not settle over time, rather they remain uniformly distributed in the solvent.
Solutions are usually transparent or translucent. They do not scatter light.
The solute and solvent are fully miscible. This means they can mix in any proportion.
Particle size:
Smaller than 1000 nm
Examples:
Saltwater (salt dissolved in water)
Soda (carbon dioxide dissolved in water)
Air (a mixture of gasses, primarily nitrogen and oxygen).
Colloids
Colloids are heterogeneous mixtures in which particles of an insoluble (unable to dissolve) substance are suspended throughout another substance. The one substance DOES NOT dissolve in the other substance.
It is important to note here that while colloids appear to be homogenous, they are actually heterogeneous mixtures when you take a look at them under a microscope.
Characteristics:
The composition of the constituents is not identical throughout the solution.
Some colloids have the ability to scatter light. This is known as the Tyndall effect.
Particles remain dispersed without settling.
Particle size:
Between 1 and 1000 nm
Examples:
Dust in the air (here the solid dust particles are suspended in a gaseous air medium)
Milk
Gelatin
Suspension
A suspension is a heterogeneous mixture in which solid particles are dispersed in a liquid or gas. These particles settle out over time when the mixture is not agitated.
Characteristics:
Particles are larger and can be seen with the naked eye.
The particles settle at the bottom when the suspension is left undisturbed.
Particle size:
Greater than 1000 nm
Examples:
Mixture of sand and water, Orange juice with pulp.
Take a look at this handy table to see how all three categories of mixtures compare to each other:
|
Solution |
Colloid |
Suspension |
|
Homogenous |
Heterogenous |
Heterogenous |
|
Particles uniformly dispersed |
Particles not uniformly dispersed |
Particles not uniformly dispersed |
|
Cannot scatter light |
Ability to scatter light |
Cannot scatter light |
|
Particles smaller than 1000 nm |
Particles between 1 and 1000 nm |
Particles greater than 1000 nm |
|
Particles do not settle over time |
Particles do not settle over time |
Particles settle over time |
|
Example: saltwater |
Example: dust in the air |
Example: sand in water |
So where do emulsions fit in?
When making your DIY lip balm, you are creating an emulsion. So now that you know all about solutions, colloids and suspensions, where do emulsions fit in?
An emulsion is a heterogeneous mixture where two immiscible liquids (liquids that do not normally mix) are dispersed in each other. The immiscible liquids are broken down into tiny droplets and distributed throughout the mixture. Emulsions can be temporary or permanent and they typically use an emulsifying agent to prevent separation.
An emulsion is a type of colloid
Let's look at mayonnaise as an example. Mayonnaise is an emulsion of oil and lemon juice or vinegar. Lemon juice and vinegar do not typically mix with oil. That’s where the egg yolk comes in. The addition of an egg yolk functions as an emulsifier.
Examples:
Mayonnaise, Vinaigrette, Lip balm
While all emulsions are colloids, not all colloids are emulsions. Emulsions are specifically between two immiscible liquids.
Now that you know all about mixtures and their properties, make your own emulsion in the form of a DIY lip balm. Everything you need to know is in my freebie, Empower Your Teen’s Creativity: Hands on Science Activities for Learning and Fun.
Tag me on Instagram @istiloprints so I can see your creations!
References
BYJU’s Tuition Center
https://byjus.com/chemistry/mixtures/
https://byjus.com/question-answer/is-colloidal-solution-homogeneous-or-heterogeneous/
Labster.com
https://theory.labster.com/type_mixtures/
How Stuff Works
https://recipes.howstuffworks.com/food-facts/question617.htm
