In a gas mixture of He, Ne, and Ar with a total pressure of 8.40 atm, the mole fraction of Ar is ________ if the partial pressures of He and Ne are 1.50 and 2.00 atm respectively.
pHe = 1.50 atm.
pNe = 2.00 atm.
pAr = 8.40 atm - 1.50 - 2.00 = ??
mole fraction Ar = pAr/total p.
0.58
.583
Well, since pAr = 8.40 atm - 1.50 atm - 2.00 atm, we can bring out our handy-dandy calculator and do some basic subtraction. 8.40 minus 1.50 is... 6.90, and then we subtract 2.00 from that and we get... 4.90! So, pAr is 4.90 atm.
Now, let's determine the mole fraction of Ar. We take pAr (which is 4.90 atm) and divide it by the total pressure, which is 8.40 atm. So, mole fraction of Ar = 4.90 atm / 8.40 atm. To simplify things, let's divide both numbers by 4.2, which gives us... approximately 1.16.
Therefore, the mole fraction of Ar in the gas mixture is approximately 1.16. Voilà!
To find the partial pressure of Ar, we need to subtract the partial pressures of He and Ne from the total pressure.
The given partial pressures are:
pHe = 1.50 atm
pNe = 2.00 atm
The total pressure is given as 8.40 atm.
To find the partial pressure of Ar, we subtract the partial pressures of He and Ne from the total pressure:
pAr = 8.40 atm - 1.50 atm - 2.00 atm = 4.90 atm
The partial pressure of Ar is 4.90 atm.
Next, let's find the mole fraction of Ar. The mole fraction of a component in a gas mixture is calculated by dividing the partial pressure of that component by the total pressure of the mixture:
mole fraction Ar = pAr / total pressure
Plugging in the values we have:
mole fraction Ar = 4.90 atm / 8.40 atm
After evaluating this expression, we get the mole fraction of Ar as 0.5833 (rounded to four decimal places).
Therefore, the mole fraction of Ar in the gas mixture is approximately 0.5833.