Determine the pressure of CO2 gas in the pressurized Falcon tube

Question

Determine the pressure of CO2 gas in the pressurized Falcon tube (assume the vented tube has a pressure of 1 atm, and that V and n remain constant). You will need the mass of an evacuated Falcon tube (no air) which can be calculated using partial pressures of the main components of air, O2 (21%) and N2 (79%). 

Mass of empty falcon tube =6.403 g

Mass of sealed falcon tube + CO2 gas = 6.513 g

Mass of falcon tube after releasing pressure = 6.430 g

Volume of falcon tube = 16mL

Answer 1

Approximate molar mass of air = .79*28 + .21*32 = 28.8 g/mole

The mass of CO₂ in vented tube - mass of air in "empty tube" =

6.430g - 6.403 g = m_CO2 - (28.8/44.0)m_CO2 (There are the same V and n and P for the air and CO₂, Therefore the mass of gas in the two tubes are proportional.

We can find the mass of the CO₂ in the vented flask as .07816 g

This means the evacuated tube is 6.430 - .07816 = 6.3518 g

The mass of pressurized CO₂ is 6.513 g - 6.3518 = .1612 g CO₂

The pressure in the vessel is 1 atm (.1612/.07816) = 2.062 atm. P is proportional to moles (mass) for V and T constant)

Please consider a tutor. Take care.