A 19.0-L tank of carbon dioxide gas (CO2) is at a pressure of 9.10 x 10^5 Pa and temperature of 21.0°C.?

A 19.0-L tank of carbon dioxide gas (CO2) is at a pressure of 9.10 x 10^5 Pa and temperature of 21.0°C.?


(b) Use the ideal gas law to calculate the number of moles of gas in the tank: __7.07__mol

P = 9.10 × 10⁵ Pa = 910 kPa
V = 19.0 L
n = ? mol
R = 8.314 J / (mol K)
T = (273.2 + 21.0) K = 294.2 K

PV = nRT
n = PV/(RT) = 910 × 19.0 / (8.314 × 294.2) mol = 7.07 mol


(c) Use the periodic table to compute the molecular weight of carbon dioxide, expressing it in grams per mole: __44.0__g/mol

Molecular weight of CO₂ = (12.0 + 16.0×2) g/mol = 44.0 g/mol


(d) Obtain the number of grams of carbon dioxide in the tank: __311__g

Mass of CO₂ in the tank = (44.0 g/mol) × (7.07 mol) = 311 g


(e) A fire breaks out, raising the ambient temperature by 224.0 K while 82.0 g of gas leak out of the tank. Calculate the new temperature and the number of moles of gas remaining in the tank: temperature: __518.2__K
number of moles: __5.21__mol

New temperature = (294.2 + 224.0) K = 518.2 K

No. of moles of gas remaining in the tank = 7.07 - (82.0/44.0) mol = 5.21 mol


(f) Using the ideal gas law, find a symbolic expression for the final pressure, neglecting the change in volume of the tank. (Use the following as necessary: ni, the initial number of moles; nf, the final number of moles; Ti, the initial temperature; Tf, the final temperature; and Pi, the initial pressure.)
Pf = __ Pi nf Tf / (ni Ti)__

PV = nRT
P /(n T) = R/V = constant, where R and V are constant
Then, Pi / (ni Ti) = Pf / (nf Tf)
Hence, Pf = Pi nf Tf / (ni Ti)


(g) Calculate the final pressure in the tank as a result of the fire and leakage: __1.18 × 10⁶__Pa

Final pressure = (9.10 × 10⁵) × 5.21 × 518.2 / (7.07 × 294.2) Pa = 1.18 × 10⁶ Pa