Chemistry Uncovered: The World of Colloids
by Yuvi K - December 16, 2023
Chemistry Uncovered: The World of Colloids
What do fog, mayonnaise, and paint all have in common? These things are all examples of colloids, a type of chemical solution made up of two different substances. Colloids are everywhere in the world around us, and can even be found in our bodies. In this article, we will explore the science behind colloids and discuss their uses.
The Basics of Colloids
At its core, a colloid is a mixture of two substances that are evenly dispersed when combined. One substance is normally a gas or liquid, while the other is a solid, liquid, or gas. The two substances don’t actually mix together, but instead are held in a state of suspension where they are evenly dispersed and can interact with one another.
The particles that make up a colloid are measured in nanometers, which can range from 1 to 1,000 nanometers. A nanometer is 1 millionth of a millimeter! The smaller the particles in a solution, the more evenly they are dispersed, and the longer it will take for the colloid to separate.
Classification of Colloids
Colloids can be classified based on the two substances they are composed of. These are:
Lyophobic Colloids
These colloids are made of metal ions and solutions like water or alcohol. They have an overall negative charge due to the presence of metal ions, which helps to keep them in suspension. Examples of lyophobic colloids include fog, sulfuric acid, and ink.
Lyophilic Colloids
These colloids are made up of molecules like sugar, which is hydrophilic (attracted to water). The molecules have a slight positive charge, which helps to keep them in suspension. Examples of lyophilic colloids include milk, gelatins, and sauces like mayonnaise.
Uses of Colloids in Everyday Life
Colloids are used in many everyday products, from food to cleaning supplies. Because of their very small particle size, colloids act like a “sponge” and can easily attract and hold dirt, bacteria, and other materials.
One of the most common uses for colloids is in paint. The particles in paint are so small that they spread evenly across surfaces and create a smooth finish. Additionally, the particles can remain suspended for a long period of time, allowing the paint to last longer without separating.
Medical researchers have also taken advantage of colloids for their ability to transport molecules and drugs quickly and efficiently to the body. For example, colloids can be injected into veins, bypassing the digestive system and allowing for the quick administration of drugs.
Conclusion
Colloids are one of the most common forms of chemical mixtures, and are found everywhere in the world around us. They are composed of two different substances that are held in suspension, and can range from nanometers in size. There are a variety of uses for colloids in everyday life, from paint to medical treatments.
The world of colloids is an ever-expanding field, and it is sure to only become more prevalent with time. Whether it be for food, cleaning supplies, or medical treatments, colloids can be found all around us!
