Respuesta :
Molar Mass = 99.7669.
To solve, first use the equation PV=nRT and solve for n, the number of moles. You do this by finding that n=PV/RT. Then plug in your values above, make sure your temperature is in kelvins by adding 273 and your volume is in liters (151.3 mL = 0.1513 L). You get that n=.006435. You can then solve for the molar mass by dividing your given mass, 0.642g, by the number of moles you solved for, .006435, and get 99.7669 g/mol
To solve, first use the equation PV=nRT and solve for n, the number of moles. You do this by finding that n=PV/RT. Then plug in your values above, make sure your temperature is in kelvins by adding 273 and your volume is in liters (151.3 mL = 0.1513 L). You get that n=.006435. You can then solve for the molar mass by dividing your given mass, 0.642g, by the number of moles you solved for, .006435, and get 99.7669 g/mol
Answer : The molar mass of unknown gas is 99.8 g/mole.
Explanation :
Using ideal gas equation:
[tex]PV=nRT\\\\PV=\frac{w}{M}RT[/tex]
where,
P = pressure of gas = 1.04 atm
V = volume of gas = [tex]151.3ml=0.1513L[/tex]
conversion used : [tex](1L=1000ml)[/tex]
T = temperature of gas = [tex]25.0^oC=273+25.0=298K[/tex]
R = gas constant = 0.0821 L.atm/mole.K
w = mass of an unknown gas = 0.642 g
M = molar mass of an unknown gas = ?
Now put all the given values in the ideal gas equation, we get:
[tex](1.04atm)\times (0.1513L)=\frac{0.642g}{M}\times (0.0821L.atm/mole.K)\times (298K)[/tex]
[tex]M=99.8g/mole[/tex]
Therefore, the molar mass of unknown gas is 99.8 g/mole.
