1) A sample of limestone is heated, and the CO2 gas released is collected in an

Question

1) A sample of limestone is heated, and the CO2 gas released is collected in an evacuated flask connected to an open-end manometer. If the atmospheric pressure is 0.9475 atm and gas pressure (Pgas) is greater than the atmospheric pressure by 25.8 torrr, calculate the gas pressure in mmHg, Pascals, and Ib/in2 2) A tank contains 651 L of compressed oxygen gas at pressure of 122 atm. Assuming the temperature remains constant, what is the volume of the oxygen (in L) at 745 mmHg? 3) A rigid plastic container holds 35.0 g of ethylene gas (C2H4) at pressure of 793 torr. What is the pressure if 5.0g of ethylene is removed at constant temperature? 4) A balloon filled with 1.26g of nitrogen has a volume of 1.12 L. Calculate the volume of the balloon after 1.26 g of helium is added at constant T and P 5) A diver has 2.2 L of air in his lungs at an air temperature of 28 C and a pressure of 0.980 atm. What is the volume of air in his lungs after he dives to a depth of 10m, while holding his breath, where the temperature is 21 C and the pressure is 1.40 atm? 6) A steel tank has a volume of 438 L and is filled with 0.885 Kh of O2. Calculate the pressure of 02 at 21 C 7) A blimp is filled with 3950 Kg of helium at 731 mmHg and 20 C. What is the volume of the blimp under these conditions? 8) Find density (g/L) of CO2 and the number of molecules per liter at 20 C and 0.9 atm. 9) Compare the density of CO2 at 0 C and 380.0 torr with its density at STP 10) An empty 149 ml flask weighs 68 g before a sample of volatile liquid is added. The flask is then placed in a hot (85C) water bath with barometric pressure at 740 torr. The liquid vaporizes and the gas fills the flask. After cooling, flask and condensed liquid together weigh 68.697 g. What is the molar mass of the liquid. 11) A chemical engineer places a mixture of noble gases consisting of 5.50 g of He, 15.0 g of Ne, and 35.0g of Kr in a piston-cylinder assembly at STP. Calculate the partial pressure of each gas 12) Solid lithium hydroxide is used to scrub CO2 from the air in spacecraft submarines. It reacts with CO2 to produce lithium carbonate and water. What mass of lithium hydroxide is required to remove 215 L of CO2 at 23 C and 0.942 atm ? 2LiOH(s) +CO2(g) --à Li2CO3(s) +H20(1)

Explanation / Answer

1) gas pressure Pgas,

Pgas = 25.8 torr + 0.9475 atm x 760 torr = 745.9 torr = 745.9 mmHg

         = (745.9/760) x 101325 = 99445.155 Pa

         = (745.9/760) x 14.7 lb/in^2 = 14.43 lb/in^2

2) at 745 mmHg/760 = 0.98 atm

using,

P1V1 = P2V2

with P2 and P1 are final and initial pressure, V2 and V1 are final and initial volumes, respectively

Volume of gas at 745 mmHg (0.98 atm) V2 = 122 atm x 651 L/0.98 atm = 81021 L

3) using,

P1/n1 = P2/n2

with, n2 = (35/28), n1 = (5/28), P2 = 793 torr, P1 = ?

pressure of ethylene gas after 5 g is removed n1 = (5 g/28 g/mol) x 793 torr/(35 g/28 g/mol) = 113.3 torr

4) Total moles of gas after addition (n2) = (1.26 g/28 g/mol)N2 + (1.26 g/4 g/mol)He = 0.36 mol

initial moles of N2 (n1) = (1.26 g/28 g/mol) = 0.045 mol

initial volume (V1) = 1.12 L

final volume (V2) = ?

using,

V2/n2 = V1/n1

final volume (V2) = 1.12 x 0.36/0.045 = 8.96 L

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.