# How to find mass through volume?

In chemistry and physics, there are often problems in which it is necessary to calculate the mass of a substance, knowing its volume. How to find mass through volume. The density table will help you with this, since in order to find the mass, it is necessary to know both the density and the volume of the substance.

If the condition of the problem does not indicate the density, you can look at the table in which there is such data on each substance. Ideally, of course, you need to learn such a table, but you can refer to the textbook on chemistry.

The rule states that the volume of a substance, multiplied by its density, is equal to the mass of a given substance. From this rule, the formula of mass through volume is derived. It looks like this: m = V * p. Where m is the mass, V is the volume, and p is the density. Knowing the number that is equal to the volume, you can see the number that will be equal to the density, multiply the data. So you can get a lot.

## Calculation example

For example, given the volume of 5 ml. The volume of a substance is calculated in such units as liters and milliliters. The substance whose mass is to be found is gelatin. Looking at the table, you can see that its density is equal to 1.3 g / ml.Now use the formula. Volume V is equal to 5 ml. It is necessary to multiply 5 ml. by 1.3 g / ml. That is: 5 * 1.3 = 6.5 grams. So m - weight is 6.5 grams. Why the gram: when multiplying the volume by the density, we have such units as milligrams. We reduce them, there are grams that represent mass.

You can use another way. You need to know or have on hand a periodic table. This method involves the use of the molar mass of the substance (in the table). It is necessary to know the formula, which states that the mass of a substance is equal to the product of the volume by the molar mass. That is, m = V * M, where V is the volume of a given substance, and M is its molar mass.