To find the volume of one mole of a substance in strong or liquid state, find its molar weight and divide into density. One mol of any gas in normal conditions has the volume of 22.4 l. In that case if conditions change, calculate the volume of one asking by means of Klapeyrona-Mendeleyev's equation.
It is required to you
- periodic table of Mendeleyev, table of density of substances, manometer and thermometer.
Instruction
1. Scoping of one of liquid or a solid body Define a chemical formula of a solid body or liquid which is studied. Then, by means of the periodic table of Mendeleyev find atomic masses of elements which enter a formula. If one element enters in a formula several times, increase its atomic mass by this number. Put atomic masses of all elements and receive the molecular mass of substance of which the solid body or liquid consists. It will be in number equal to the molar weight measured in grams on mol.
2. According to the table of density of substances find this size for material of the studied body or liquid. After that divide molar weight into density of this substance measured in g/cm³ by V=M/ρ. As a result receive the volume of one asking in cm³. If the chemical formula of substance remained the unknown, to determine the volume of one it asking it will be impossible.
3. Scoping of one of a gazayesla gas is in so-called normal conditions, with a pressure of 760 mm Hg. and 0ºС, the volume of one asking him, it is not dependent on a chemical formula it is equal to 22.4 l (Avogadro's law determining the molar volume of gas). To transfer it to cm³ increase by 1000, and in m³ - divide into the same number.
4. If gas is not in normal conditions, measure by means of the manometer its pressure in pascals and temperature in degrees Kelvin for what to temperature taken by the thermometer in degrees Celsius add number 273.
5. From Klapeyrona-Mendeleyev's equation P·V = υ\• R · T, express the gas volume relation on its amount of substance. It will also be the volume of one asking which it is equal to the work of temperature of gas on a universal gas constant which is equal 8.31, divided into pressure of V/υ=R•T/P gas. Receive result in m³ on mol. To transfer value to cm³, increase the received number by 1000000.