Question

Sulfur hexafluoride gas is collected at 26.0 °C in an evacuated flask with a measured volume of 35.0 L. When all the gas has been collected, the pressure in the flask is measured to be 0.300 atm . Calculate the mass and number of moles of sulfur hexafluoride gas that were collected. Be sure your answer has the correct number of significant digits. mass: s mole

Answer 1

Moles of sulfur hexafluoride gas = 0.428 moles

Mass of sulfur hexafluoride gas = 62.5 g

Step-by-step explanation:

Given that:

Pressure = 0.300 atm

Temperature = 26 °C

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15

So,

T = (26 + 273.15) K = 299.15 K

Volume = 35.0 L

Using ideal gas equation as:

`PV=nRT`

where,

P is the pressure

V is the volume

n is the number of moles

T is the temperature

R is Gas constant having value = 0.0821 L.atm/K.mol

Applying the equation as:

0.300 atm × 35.0 L = n × 0.0821 L.atm/K.mol × 299.15 K

⇒n = 0.4275 moles

Moles of sulfur hexafluoride gas = 0.428 moles

Molar mass of sulfur hexafluoride gas = 146.06 g/mol

The formula for the calculation of moles is shown below:

`moles = (Mass\ taken)/(Molar\ mass)`

Thus,

`0.428= (Mass)/(146.06\ g/mol)`

Mass of sulfur hexafluoride gas = 62.5 g