You will need
• paper;
• calculator;
• - handle;
• - the gas pressure (the conditions of the problem or in a table);
• - the temperature at which it is necessary to determine the density
• periodic table of elements.
Instruction
1
Write down on paper the equation Mendeleev-Clapeyron ideal gas law: PV=(m/m)RT . It can be used for saturated steam, but once the gas density becomes comparable with the density of saturated steam, this equation cannot be used in the calculation – it will show an incorrect result. Other gas laws, is not subject to saturated steam.
2
From the recorded output of the equation the density of saturated steam. It equals mass divided by volume. Therefore, the equation is converted to: P= (p us. pair/M)RT. Here you can write a formula to find the density of saturated steam: p= PM/RT . Here P is the gas pressure. Its tabular value is usually given in the problem statement and depends on temperature. If not given, find the table for your temperature. R is the universal gas constant, equal to 8,31 j/(K*mol).
3
If you are aware of temperature in degrees Celsius, ensure that it is in degrees Kelvin (denoted by K). To do this, add 273 to the temperature as -273 is absolute zero on the Kelvin scale.
4
Find the molar mass of the liquid M. It can be calculated by using the periodic table. Molar mass of a substance is numerically equal to the molecular. Find in the table of atomic masses of all elements contained in the substance, and multiply by the number of respective atoms in the molecule. The sum of the values will give the molecular weight of the substance.
5
Substitute in the last expression, all the known values. The pressure P is necessary to substitute in PA. If the condition given in kPa, multiply it by 1000. Molar mass by substituting in kg/mole (divide by 1000) as in the periodic table it is given in g/mol. Using a calculator, calculate the density of saturated steam. The result is in kg/m3.