The mass percent of a three component gas sample is 95.2% PF5, 1.40% C2H2 and 3.40% C3H6. Calculate the partial pressure (atm) of PF5 if the total pressure of the sample is 570.0 torr.
I would approach this problem by assuming a convenient sample of the gas (say 100 g), convert each to grams, then to moles, then determine the mole fraction of PF5.
Use Raoult's Law to finish.
P = XPo
By the way, it helps us if you DON'T use different names for posting various questions.
CALCULATE THE NUMBER OF MOLES FOR 12.7 MG OF IRON SULFATE
To calculate the partial pressure of PF5, we first need to find the moles of each component in the gas sample.
1. Convert the mass percent of each component to grams:
- Mass of PF5 = 95.2% of total mass
- Mass of C2H2 = 1.40% of total mass
- Mass of C3H6 = 3.40% of total mass
2. Calculate the moles of each component using their molar masses:
- Moles of PF5 = (Mass of PF5 in grams) / (Molar mass of PF5)
- Moles of C2H2 = (Mass of C2H2 in grams) / (Molar mass of C2H2)
- Moles of C3H6 = (Mass of C3H6 in grams) / (Molar mass of C3H6)
3. Calculate the total moles of the gas sample:
- Total moles = Moles of PF5 + Moles of C2H2 + Moles of C3H6
4. Calculate the partial pressure of PF5 by multiplying its moles by the total pressure and dividing by the total moles:
- Partial pressure of PF5 = (Moles of PF5 / Total Moles) * Total Pressure
Let's calculate the partial pressure of PF5:
1. Molar mass of PF5: 125.97 g/mol (Phosphorous pentafluoride)
Molar mass of C2H2: 26.04 g/mol (Acetylene)
Molar mass of C3H6: 42.08 g/mol (Propene)
2. Calculate the mass of each component:
- Mass of PF5 = 95.2% * (570.0 torr/760 torr) * (total mass in grams)
- Mass of C2H2 = 1.40% * (570.0 torr/760 torr) * (total mass in grams)
- Mass of C3H6 = 3.40% * (570.0 torr/760 torr) * (total mass in grams)
3. Calculate the moles of each component:
- Moles of PF5 = Mass of PF5 / Molar mass of PF5
- Moles of C2H2 = Mass of C2H2 / Molar mass of C2H2
- Moles of C3H6 = Mass of C3H6 / Molar mass of C3H6
4. Calculate the total moles:
- Total Moles = Moles of PF5 + Moles of C2H2 + Moles of C3H6
5. Calculate the partial pressure of PF5:
- Partial pressure of PF5 = (Moles of PF5 / Total Moles) * Total Pressure
By following these steps, we can determine the partial pressure of PF5 in the given gas sample.