36 problems
1PRACTICE PROBLEMA 3.00-L closed vessel contains 2.75 g of acetone (C3H6O) with a vapor pressure of 282 mmHg at 30°C. Determine if there will be any liquid present in the vessel. If so, calculate the mass of the liquid.
2PRACTICE PROBLEMAt −45.4°C, the vapor pressure of ammonia is 400 mmHg. Is there a liquid present if 1.05 g of ammonia is enclosed in a 2.00-L vessel? If so, determine the mass of liquid ammonia present.
3PRACTICE PROBLEMMining has occasionally used zinc carbonate (ZnCO3) as an "explosive." Drilling a hole, inserting zinc carbonate, a trace amount of gunpowder, a fuse, and plugging the hole are the steps. When ignited, this creates a tremendous amount of pressure. Assume that 780 g of zinc carbonate are put in a cavity that has a volume of 0.350 L, and that the zinc carbonate is heated to 650 K by the gunpowder that has been ignited. How much pressure is inside the hole at the end?
4PRACTICE PROBLEMThe reaction of oxalic acid (H2C2O4) and potassium chlorate (KClO4) produces potassium carbonate (K2CO3), water, gas X, and gas Y:H2C2O4(aq) + KClO4(aq) → K2CO3(aq) + H2O(l) + X(g) + Y(g)The gases were collected and placed in a 1.50 L vessel at 27.0°C. The final pressure of the vessel is 552 mmHg. Calculate the total moles of gas present.
5PRACTICE PROBLEMThe following apparatus shows three enclosed 0.500 L bulbs connected by stopco*cks. Bulb X at 200°C and has a total pressure of 650 mmHg contains Br2(g), I2(g), and Cl2(g). Bulb Y and Bulb Z are both empty and held at a temperature of 95.0°C and 25.0°C, respectively. Initially, the stopco*cks are closed, and assume that the volume of the lines joining the bulbs is negligible.When the stopco*ck between X and Y opened and was allowed to reach equilibrium, X and Y has a total pressure of 270 mmHg. Calculate the moles of I2 present in the system.Useful information:
6PRACTICE PROBLEMAn LPG or liquefied petroleum gas is made up of a mixture of propane (C3H8) and butane (C4H10). Assume that the mole fractions of propane and butane in a certain LPG mixture are 0.822 and 0.178, respectively. A 36.5 g sample of an LPG mixture has a volume of 10.0 L at 15.0°C. Calculate the pressure (in atm) of the mixture.
7PRACTICE PROBLEMAt 298 K, the reaction 2 PCl3(g) + O2(g) → 2 POCl3(g) Kc = 16 occurs in the atmosphere with . With 2.4 mol PCl3 and 3.1 mol O2 and an initial total pressure of 1.38 atm, a gas mixture is created. What is the container's volume?
8PRACTICE PROBLEMA driver who is almost out of fuel may claim to be "running on fumes." What is the maximum distance a taxi could travel if its 30.0-gallon gas tank contained only diesel vapor and it gets 20.0 miles per gallon on diesel? Assume that diesel has a density of 0.830 g/mL, an average molar mass of 167 g/mol, a pressure of 246 mm Hg, and a temperature of 40 °C.
9PRACTICE PROBLEMArgon in the atmosphere has a partial pressure of 946.4 Pa at the standard sea level temperature of 288 K. Determine the number of argon atoms present in 1.00 liter of argon.
10PRACTICE PROBLEMAt 26°C, a 556 mL gas tank in a laboratory contains 43.6 g of argon. Calculate the mass of argon (in g) that must be released in order to reduce the pressure to 4.66 MPa. Assume that argon gas behaves ideally.
11PRACTICE PROBLEMWhat are the mass of hydrogen in a hydrogen-filled balloon and the mass of helium in a helium-filled balloon if the volume of the balloon is 2944 mL with a total pressure of 200 psi at 27 °C? What is the mass difference between the two?
12PRACTICE PROBLEMUnder which conditions will one mole of ideal gas occupy less volume?(a) P = 0.74 atm, T = 250 K(b) P = 0.32 atm, T = 180 K
13PRACTICE PROBLEMThe relative humidity of air in a 5 m × 5 m × 5 m room is 26% at 25 ºC. Calculate the number of water molecules present in the room. The relative humidity is the ratio of the partial pressure of water in the air to the vapor pressure of water at the given temperature.
14PRACTICE PROBLEMIn 2021, the concentration of CO2 in the Earth's atmosphere was measured at 412 ppm. Calculate the number of CO2 molecules in 1.5 L of air at 5000 m above sea level, with an atmospheric pressure of 0.53 atm and temperature of 15 ºC.
15PRACTICE PROBLEMA sample of HI(g) was placed in a 500 mL flask and allowed to decompose to H2(g) and I2(g) at 250 ºC and 1.10 atm. Calculate the initial mass of HI(g) in the flask.
16PRACTICE PROBLEMA vessel at 35.0°C consists of 0.155 g of water. At 35.0°C, the vapor pressure of water is 42.2 mmHg. In order to make sure that no liquid water is present in the vessel, what should be the minimum volume of the vessel?
17PRACTICE PROBLEMSome air conditioners have a dry mode that removes moisture from the air like a dehumidifier. The dimensions of an office in a building are 9.0 m × 6.0 m × 5.5 m. The temperature outside is 27.0°C and the partial pressure of water in the air at this temperature is 73.0% of the vapor pressure of water. If the air volume in the office is cycled through the air conditioner and all of the water must be removed, determine the mass of the water removed. [vapor pressure of water at 27.0°C = 26.7 mmHg]
18PRACTICE PROBLEMCement is the source of about 8% of the world's carbon dioxide (CO2) emissions. The manufacture of cement produces about 0.9 kg of CO2 for every kg of cement. In 2021, 92 million metric tons of cement were produced in the United States. Calculate the volume of CO2 emitted by cement production in the U.S. in 2021. Assume that it behaves as an ideal gas under the conditions of 1 atm and 25°C.
19PRACTICE PROBLEMA mothball (Naphthalene, C10H8) weighing 130.0 g was placed inside a 10 L vacuum container. The container was then slowly heated to 80°C. After it reached the temperature the mothball fully sublimes to gas. Calculate the pressure inside the container.
20PRACTICE PROBLEMN-Methylpyrrolidone (C5H9NO) is a solvent used in paint and coating removal. It can be very harmful to one's health causing headache, stomach pain, nausea, and vomiting. The maximum allowable concentration for N-Methylpyrrolidone is 20 ppm (1 mole C5H9NO per 106 mole gas). Calculate the mass of C5H9NO allowable in a room that has the dimensions 4.0 m, 10.0 m, and 4.0 m at 25°C and 1.0 atm.
21PRACTICE PROBLEMIn 5 mins, an average male person consumes 214 mL of oxygen at 1.00 atm and 25.0 °C per kg of body weight.Calculate the moles of oxygen consumed by a 70.0 kg male in 8 hours.
22PRACTICE PROBLEMMothballs (naphthalene, C10H8) with a mass of 36.4 g sublimes into a gasbag. Calculate the volume of the gasbag at 84.0°C and 765 mmHg. Assume no gas is lost upon sublimation.
23PRACTICE PROBLEMA 250-mL cylinder filled with krypton gas at 2.6 atm and 278 K. Determine the fraction of the volume that is occupied by Kr atoms. Krypton atom has a radius of 2.02×10-8 cm. Assume that atoms are spheres.
24PRACTICE PROBLEMA 20.0 L-vessel was charged with 41.3 g of chlorine gas at a temperature of 315 K. Calculate the pressure in the vessel.
25PRACTICE PROBLEMIf 0.24 moles of a gas has a pressure of 0.62 atm and a volume of 5.3 L, find the temperature of the gas.
26PRACTICE PROBLEMAt 27.0°C, a bicycle tire that has a volume of 985 mL is filled with nitrogen gas to a total pressure of 96.5 psi. Find the mass of nitrogen in the tire.
27PRACTICE PROBLEMThe decomposition of a 1.67 g sample of an unknown chlorofluorocarbon produces 407 mL of chlorine gas at 300 K and 746 mmHg. Determine the mass percent chlorine in the unknown chlorofluorocarbon.
28PRACTICE PROBLEMConsider an air-filled tire that has a volume of 1250 mL, filled to a total pressure of 85.5 psi, and a temperature of 26°C. Calculate the mass of the air in the tire. Assume that the average molar for air is 28.8 g/mol.
29PRACTICE PROBLEMWhat volume 12.5 g of argon gas occupies at a pressure of 1.22 atm and a temperature of 352 K? If the sample were 12.5 g of helium, would the volume be different under identical conditions?
30PRACTICE PROBLEMApproximately 0.04% of the Eart's atmosphere is made up of carbon dioxide. How many CO2 molecules would be in a 3.4 L sample collected from the atmosphere at sea level (1.00 atm) on a warm day (30°C)?
31PRACTICE PROBLEMAir is made up of approximately 21.0% oxygen and 78.0% nitrogen. A 25.0-L sample of air is collected at 1.00 atm and 30.0°C. Determine the number of molecules of oxygen in the sample.
32PRACTICE PROBLEMThe volume of air that an infant's lungs can hold is 0.150 L. Assuming that air behaves ideally and has an average molar mass of 29.0 g/mol, calculate the mass of air that an infant's lungs can hold at 25.0°C and 1.00 atm.
33PRACTICE PROBLEMAt a pressure of 1.5×104 kPa, calculate the number of molecules of oxygen gas stored in a cylinder tank with a volume of 40 L at a temperature of 50°C.
34PRACTICE PROBLEMA mass of 8.0 g of nitrous oxide gas (N2O) is contained in a cartridge with a volume of 10.0 mL at 25.0°C. It is advised not to store it at temperatures above 50.0°C as indicated in the packaging. Calculate the pressure when the cartridge reaches a temperature of 50.0°C.
35PRACTICE PROBLEMA mass of 8.0 g of nitrous oxide gas (N2O) is contained in a cartridge with a volume of 10.0 mL at 25.0°C. Calculate the pressure in the cartridge.
36PRACTICE PROBLEMAt 273 K and 1 atm pressure, 1 mol of an ideal gas occupies 22.4 L. In the figure below, the temperature is lower at 10 km altitude than at 50 km. Does this mean that one mole of an ideal gas would occupy less volume at 10 km than at 50 km?
