Answer:
Pressure in the second container is 0,673 atm
Cl₂ is gas with highest density, He have the highest average velocity, number of molecules is equal for all gases.
Explanation:
Using PV = nRT is possible to obtain the moles of gas in a container using:
n = PV/RT (1)
Where:
P is pressure: 645torr* (1atm/760torr)= 0,845 atm
V is volume: 50,0mL = 0,0500L
R is gas constant: 0,082 atmL/molK
And T is temperature: 25°C + 273,15 = 298,15K
Replacing in (1)
n = 1,73x10⁻³ moles
As the entire gas is transferred to a new container (That is every mole was transferred), pressure is:
P = nRT/V
As temperature is 35°C + 273,15 = 308,15K and Volume is 65,0mL = 0,065L
P = 1,73x10⁻³ mol×0,082atmL/molK×308,15K/0,065L = 0,673 atm
Moles contained in the flask are:
n = PV/RT
P = 1atm; V = 1,0L; R = 0,082atmL/molK: T = 273,15K
n = 0,045 moles
As density is ratio between mass and volume and the volume is the same in the four flasks the gas that have the higher mass will be the the highest density.
Molar mass of He is 4g/mol; Cl₂ = 70,9g/mol; CH₄ = 16,05g/mol; NH₃ = 17,03g/mol
As Cl₂ has more mass per mol, will be the gas with the highest density.
Average velocity is:
v = √RT/M
As R is gas constant and temperature is constant, molar mass (M) is the relevant item, that is velocity is inversely proportional to molar mass.
That means the lower molar mass, the highest velocity. That means He have the highest average velocity.
As number of moles is the same for each gas, number of molecules is equal for all gases.
I hope it helps!
