Question

If there are 3 moles of gas A, 4 moles of gas b and 5 moles of gas c I'm a mixture of gases and the pressure A is found to be 2.5 atm, what is the total pressure of the sample of gases

Answer 1

Total pressure = 10 atm

Step-by-step explanation:

The excersise can help to understant the concept of mole fraction

Mole fraction is defined as:

moles of gas / Total moles = pressure of that gas / Total pressure

Both can be summed.

Sum of moles of each gas in the mixture = Total moles

Sum of pressures of each gas in the mixture = Total pressure

Those, are laws for gases.

Total moles: 3 mol of gas A + 4 moles of gas B + 5 moles of C

= 12 total moles

Pressure of A is 2.5 atm.

We replace data at the mole fraction relation

moles of A / total moles = Pressure of A / Total pressure

3 moles / 12 moles = 2.5 atm / Total pressure

Total pressure = 2.5 atm / (3mol/12mol)

Total pressure = 10 atm