Topic 3 Concentration of solution

Topic 3

concentration of solution

We all have this kind of life experience: when adding 1 scoop of sugar and 2 scoops of sugar to two cups of equal amounts of water, the sweetness of the two cups of sugar water is different after it is completely dissolved different. Then, how to quantitatively express the concentration of a solution in chemistry?

For colored solutions, you can judge whether the solution is thick or thin according to the depth of the color. Dividing a solution into a concentrated solution and a dilute solution is rather rough and cannot accurately indicate how much solute is contained in a certain amount of solution. In practical applications, it is often necessary to accurately know the amount of solute contained in a certain amount of solution, that is, the concentration of the solution. For example, when applying pesticides, the amount of pesticides contained in a certain amount of liquid medicine should be known more accurately. If the liquid medicine is too thick, it will poison the crops; if the liquid medicine is too thin, it will not be able to kill insects and sterilize effectively. Therefore, we need to know exactly the concentration of the solution.

There are many ways to express the concentration of a solution. Here we mainly introduce the mass fraction of the solute.The mass fraction of a solute in a solution is the ratio of the mass of the solute to the mass of the solution.

After finishing this topic, you should know

The mass fraction of a solute in a solution is the ratio of the mass of the solute to the mass of the solution .