Question

Review I Constants I Periodic Table Learning Goal: A mixture of He. Ar. and Xe has a total pressure of 2.10 atm. The partial pressure of He is 0.300 atm, and the partial pressure of Ar is 0.450 atm. What is the partial pressure of Xe? To use partial pressure in gas law calculations. hts In a mixture of gases, the total pressure of the gas mixture is equal to the sum of the partial pressures of the intiidual nasns Fne avamnla if une havn a mivtara nf Express your answer to three significant figures and Include the appropriate units. View Available Hint(s) Figure 1 of 1 Value Pe Units Submit ive Part B A volume of 18.0 L contains a mixture of 0.250 mole N2.0.250 mole Oz, and an unknown quantity of He. The temperature of the mixture is 0 C, and the total pressure is 1.00 atm. How many grams of helium are present in the gas mixture?

Answer 1

Total pressure is equal to some of partial pressure due to all gases , in this case

P( total ) = P ( He ) + P ( Ar ) + P ( Xe )

2.10 atm = 0.30 atm + 0.45 atm + P ( Xe )

so P ( Xe ) = 1.35 atm

part - B

Let x moles of He are present in mixture

P ( total ) = n ( total ) R T / V

1 atm ={ ( 0.25 mol + 0.25 mol + x mol ) x 0.0821 Lt atm mol^-1 K^-1 x 273 K }/ 18 litre
solving this x = 0.3035 mol He

weight ( He ) = mol x molar mass = 0.3035 mol x 4 gm mol^-1= 1.214 gm