It is possible to transfer body weight to volume in case its density is known. It for each concrete substance or material is found according to the special table. Knowing the weight and density of any body it is possible to calculate its volume, having found their relation.

## It is required to you

- - scales;
- - table of density of substances;
- - Mendeleyev's table;
- - thermometer;
- - manometer.

## Instruction

1. Define substance of which the body which volume is measured is made. According to the special table find its density. Find body weight by means of scales. If body weight is measured in grams, then take density in g/cm³. If the body rather massive, and its weight is measured in kilograms, density take in kg/m³.Чтобы to find the volume of any body, it is necessary to divide its weight into V=m/ρ density. In the first case the volume will be in cm³, and in the second – in m³.

2. If not the weight, but body weight (force operating on a support or a suspension of the body which is based in gravitational field of Earth) is known, then find body volume through this size. For this purpose according to the table find density of substance of which the body consists. In this case take value of density in kg/m³. To find body volume, divide its weight into 9.81 (acceleration of gravity) and density of V=P / (g•ρ). The result will be in m³.

3. If the mass of gas is known, its volume can be found, using Klapeyrona-Mnedeleev's equation. It is fair for the vast majority of real gases. Determine the molar mass of gas which volume needs to be measured, using Mendeleyev's table. Consider the fact that molecules of the majority of plain gases diatomic. If the mass of gas is measured in kilograms, then and molar weight has to be received in kg/mol. If in grams, then, respectively, in g/mol.

4. Take temperature in kelvins (absolute temperature) of gas by means of the thermometer. For this purpose take temperature in degrees Celsius and add to it number 273. Measure by the manometer gas pressure in pascals. To find gas volume, find the work of its weight on number 8.31 (universal gas constant) and value of temperature of gas. Consistently divide the received result into the molar mass of gas and its pressure of V= (m· R·T) / (M•P). In this case the volume of gas will be measured in m³.