# Concentration of Solutions: Definition & Levels

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Solubility and Solubility Curves

### You're on a roll. Keep up the good work!

Replay
Your next lesson will play in 10 seconds
• 0:04 What is a Solution?
• 0:59 Dilute or Concentrated
• 2:22 Calculating Concentration
• 3:43 Example
• 5:05 Lesson Summary

Want to watch this again later?

Timeline
Autoplay
Autoplay
Speed

#### Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Laura Foist

Laura has a Masters of Science in Food Science and Human Nutrition and has taught college Science.

In this lesson, we learn about solutions and what makes up a solution. We also look at solution concentration levels and how to calculate the concentration of a solution.

## What is a Solution?

In everyday life we refer to a solution as a way to solve a problem, but in science, solution can mean something else. A solution is a combination of two or more compounds. Typically, we refer to these compounds as the solvent or the solute.

A solvent is the material used to dissolve another material into it. A solute is what is being dissolved into the solvent. For example, we can have a solution of sugar water. In this example, the solvent is the water and the solute is the sugar.

When we talk about the concentration of a solution, we are typically referring to the concentration of the solute in a solvent (in other words, how much solute there is in comparison to solvent).

Water (a solvent) can only hold so much solute (such as sugar) before the solute can no longer dissolve into the solvent. In this case, the solute will fall out of solution.

## Dilute or Concentrated

A solution can be dilute or concentrated. A dilute solution is a solution that has very little solute in the solvent. This is often done to make the solute less potent, such as in the case of hydrochloric acid. Hydrochloric acid can be very dangerous, but if it is dilute then it is not as dangerous to use. Its dilute form makes it much easier to work with.

A concentrated solution is a solution where the solvent has a lot of solute in the solution. A solution that is filled to capacity is called a saturated solution. There are many compounds that are not active unless they are dissolved into solution, yet we still want the full potency of the solute. In these cases, we will use a concentrated solution.

It won't do us any good to fill the solvent beyond its saturation point, as the excess solute will simply fall out of the solution. But, we can experiment to determine what is the maximum that a solvent can hold before it reaches its saturation level, which is based on the solubility, or how easily it goes into the solution of a solute.

Based on our needs, we can have a solution on a continuum between dilute and concentrated. Maybe we want to only slightly dilute a compound. We won't fill the solvent to its maximum, but we might put in slightly less of the solute than the maximum.

## Calculating Concentration

Concentration can be calculated as long as you know the moles of solvent per liter, or molarity. For example, we might say: ''a 1 M solution of hydrochloric acid.'This means that there is 1 mole of hydrochloric acid per liter of solution.

So what does that mean and how do we know that there is 1 mole in the liter of solution?

First let's review what a mole is. This is not the blind animal that lives in the ground. Instead it is referring to a specific number of molecules. In fact, it is referring to 6.02 x 10^23 molecules of atoms. We could just as easily refer to a dozen hydrochloric acid molecules if we only wanted to talk about 12 molecules of hydrochloric acid.

To unlock this lesson you must be a Study.com Member.

### Register to view this lesson

Are you a student or a teacher?

#### See for yourself why 30 million people use Study.com

##### Become a Study.com member and start learning now.
Back
What teachers are saying about Study.com

### Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.