Q&A Hero

Q: A 19.3-g mixture of oxygen and argon is found to occupy a volume of 16.2L when measured at 675.9mmHg and 43.4oC. What is the partial pressure of oxygen in this mixture? A) 401 mmHg B) 338 mmHg C) 274 mmHg D) 437 mmHg E) 239 mmHg

Q: A 24.1-g mixture of nitrogen and carbon dioxide is found to occupy a volume of 15.1L when measured at 870.2mmHg and 31.2oC. What is the mole fraction of nitrogen in this mixture? A) 0.539 B) 0.500 C) 0.461 D) 0.426 E) 0.574

Q: The partial pressures of CH4, N2, and O2in a sample of gas were found to be 155mmHg, 476mmHg, and 669mmHg, respectively. What is the mole fraction of nitrogen? A) 20.9 B) 0.880 C) 0.515 D) 0.410 E) 0.366

Q: In a mixture of argon and hydrogen, occupying a volume of 1.66L at 910.0mmHg and 54.9oC, it is found that the total mass of the sample is 1.13g. What is the partial pressure of argon? A) 455 mmHg B) 319 mmHg C) 866 mmHg D) 591 mmHg E) 43.7 mmHg

Q: What is the volume occupied by a mixture of 0.522mol of N2 and 0.522mol of O2 gases at 0.83atm and 42.7ºC?A) 9.79 x102LB) 32.6 LC) 2.20 LD) 4.41 LE) 16.3 L

Q: A vessel with a volume of 32.5L contains 2.80g of nitrogen gas, 0.403g of hydrogen gas, and 79.9g of argon gas. At 25ºC, what is the pressure in the vessel?A) 63 atmB) 256.2 atmC) 1.73 atmD) 0.145 atmE) 0.87 atm

Q: The following equation represents the oxidation of ammonia, NH3.4NH3(g)+5O2(g)→4NO(g)+6H2O(g)At the same temperature and pressure, what is the maximum volume of nitrogen monoxide that can be obtained from 4.55x102L of ammonia and 4.55x102L of oxygen?A) 1.02 x103LB) 2.02 x102LC) 3.64 x102LD) 9.10 x102LE) 4.55 x102L

Q: Calcium nitrate will react with ammonium chloride at slightly elevated temperatures, as represented in the equation below.Ca(NO3)2(s)+2NH4Cl(s)→2N2O(g)+CaCl2(s)+4H2O(g)What is the maximum volume of N2O at STP that could be produced using a 3.40-mol sample of each reactant?A) 9.28 x102LB) 152 LC) 1.31 x10-2LD) 76.2 LE) 22.4 L

Q: The following equation represents the partial combustion of methane, CH4.2CH4(g)+3O2(g)→2CO(g)+4H2O(g)At constant temperature and pressure, what is the maximum volume of carbon monoxide that can be obtained from 3.39x102L of methane and 1.70x102L of oxygen?A) 5.09 x102LB) 3.39 x102LC) 1.19 x103LD) 1.13 x102LE) 6.78 x102L

Q: If 379.8mL of nitrogen gas, measured at 628.4mmHg and 29.7oC, reacts with excess iodine according to the following reaction, what mass of nitrogen triiodide is produced?N2(g)+3I2(s)→2NI3(s)A) 0.354 gB) 4.99 gC) 2.49 gD) 9.98 gE) 102 g

Q: What volume of ammonia gas, measured at 660.3mmHg and 58.2oC, is required to produce 6.46g of ammonium sulfate according to the following balanced chemical equation?2NH3(g)+H2SO4(aq)→(NH4)2SO4(s)A) 0.000781 LB) 0.00312 LC) 0.765 LD) 11.9 LE) 3.06 L

Q: In which of the following reactions will the pressure increase upon completion of the reaction at constant temperature?A) C(s) + O2(g) →CO2(g)B) 2NO(g) + O2(g) →2NO2(g)C) C2H6O(l) + 3O2(g) →2CO2(g) + 3H2O(l)D) 4NH3(g) + 5O2(g) →4NO(g) + 6H2O(g)E) Cl2(g) + 3F2(g)→2ClF3(g)

Q: What is the total volume of gases produced at 819K and 1.00 atm pressure when 320g of ammonium nitrite undergoes the following decomposition reaction?NH4NO2(s)→N2(g)+2H2O(g)A) 3 x22.4 LB) 22.4 LC) 15 x22.4 LD) 5 x22.4 LE) 45 x22.4 L

Q: A high temperature reaction vessel is charged with 0.5860 mol of iron powder and 35.1 L of oxygen gas at standard temperature at pressure. On heating, the iron and oxygen react according to the balanced reaction below.4Fe(s) + 3O2(g) → 2Fe2O3(s)After the reaction vessel is cooled, and assuming the reaction goes to completion, what volume of oxygen remains?A) 25.3 LB) 35.1 LC) 17.6 LD) 9.84 LE) 0.293 L

Q: A 22.4 L high pressure reaction vessel is charged with 0.3910 mol of iron powder and 1.20 atm of oxygen gas at standard temperature. On heating, the iron and oxygen react according to the balanced reaction below.4Fe(s) + 3O2(g) → 2Fe2O3(s)After the reaction vessel is cooled, and assuming the reaction goes to completion, what pressure of oxygen remains?A) 0.903 atmB) 1.196 atmC) 0.675 atmD) 0.293 atmE) 0.196 atm

Q: The balanced chemical equation for the conversion of nitrogen to ammonia is:2N2(g) + 3H2(g) →2NH3(g)Which of the following statements concerning this chemical equation is/are correct?1) In a 22.4 L container at standard temperature, 2 atm of nitrogen gas will react with 3 atm of hydrogen gas to produce 2 atm of ammonia gas.2) At standard pressure and temperature, 22.4 L of nitrogen gas will react with 22.4 L of hydrogen gas to produce 22.4 L of ammonia gas.3) At standard pressure and temperature, 44.8 L of nitrogen gas will react with 67.2 L of hydrogen gas produce 22.4 L of ammonia gas .A) 1 onlyB) 2 onlyC) 3 onlyD) 1 and 2E) 1, 2, and 3

Q: An excess of sodium hydroxide is treated with 2.4L of dry hydrogen iodide gas measured at STP. What is the mass of sodium iodide is formed? A) 1.20 g B) 32.1 g C) 16.1 g D) 19 g E) 360 g

Q: An unknown gaseous hydrocarbon consists of 85.63% carbon by mass. A 0.335-g sample of the gas occupies a volume of 0.107L at STP. What is the identity of the gas? A) C5H10 B) C6H12 C) C7H14 D) CH2 E) C4H8

Q: At 28ºC and 452mmHg, an unknown pure gas has a density of 0.674g/L. Which of the following gases could be the unknown gas?A) F2B) C3H6C) N2OD) NeE) N2

Q: It is found that at 27ºC and 1.14atm pressure, 2.22L of gas has a mass of 3.49g. Its molar mass isA) 46.2 g/mol.B) 34.0 g/mol.C) 29.4 g/mol.D) 30.6 g/mol.E) 39.8 g/mol.

Q: At 540.5mmHg and 40.2oC, a 8.18-L sample of a hydrocarbon gas has a mass of 9.98 g. What is the formula of the gas?A) C2H2B) C3H8C) C3H6D) C2H4E) C2H6

Q: A 1.50-L sample of a gas at STP has a mass of 4.75g. What is one possible formula of the gas?A) N2F4B) NF3C) NCl3D) NHF2E) NO2

Q: The density of a gas is 1.96g/L at STP. What is its molar mass? A) 65.2 g/mol B) 58.9 g/mol C) 11.4 g/mol D) 22.4 g/mol E) 43.9 g/mol

Q: A 1.00-L sample of a gas at STP has a mass of 1.16g. The molar mass of the gas is A) 5.18 g/mol. B) 26.0 g/mol. C) 22.4 g/mol. D) 44.8 g/mol. E) 193 g/mol.

Q: The density of O2 gas at 4ºC and 1.57atm isA) 153 g/L.B) 35.2 g/L.C) 2.21 g/L.D) 68.8 g/mL.E) 0.453 g/L.

Q: The density of ethane, C2H6(30.1 g/mol), at 32ºC and 1.31atm pressure isA) 1.57 g/L.B) 19.2 g/L.C) 1.34 g/L.D) 0.635 g/L.E) 0.162 g/L.

Q: Which of the following gases has the greatest density at 2.5 atm and 25ºC?A) C3H8B) SO2C) N2OD) O2E) NF3

Q: A mixture consisting of 0.120mol N2, 0.018mol O2, 0.112mol CH4, and an unknown amount of CO2 occupies a volume of 9.04L at 25ºC and 1.17atm pressure. How many moles of CO2 are there in this sample?A) 0.750 molB) 0.182 molC) 2.06 molD) 4.90 molE) 0.432 mol

Q: The number of molecules in 1.0 L of air at 0ºC and 1.0 atm pressure isA) between 1020 and 1021.B) between 1023 and 6 x1023.C) between 1022 and 1023.D) less than 1020.E) between 1021 and 1022.

Q: A 3.80-L cylinder contains 6.83g of methane, CH4, at a pressure of 3320mmHg. What is the temperature of the gas?A) 475 ºCB) 202 ºCC) 748 ºCD) 3240 ºCE) "62.4 ºC

Q: Which of the following samples has the fewest moles of gas?A) 1.00 L of CH4 at 10ºC and 1.00 atmB) 1.00 L of Ar at -10.0ºC and 1.00 atmC) 1.00 L of NH3 at STPD) 1.00 L of H2 at 0.0ºC and 1.56 atmE) 1.00 L of HCl at 30ºC and 1.00 atm

Q: The following gases are stored in identical flexible containers at 25ºC and 1.00 atm pressure. Order the gases from highest to lowest density.1) 200 g propane, C3H82) 100 g carbon dioxide, CO23) 50 g nitrous oxide, N2OA) 1 2 3B) 3 > 2 > 1C) 1 > 2 > 3D) 2 > 1> 3E) 1 > 2 3

Q: Which of the following statements is incorrect regarding a 320-g sample of gaseous sulfur dioxide at 0ºC and 760 mmHg pressure?A) The density of the gas is 2.86 g/L.B) There are 5 x6.02 x1023atoms of oxygen present.C) There are 5 mol of gas present.D) The molar mass of the gas is 64 g/mol.E) The volume of the gas is 112.1 L.

Q: How many moles of gas are in a gas sample occupying 1.48L at 591mmHg and 302K?A) 35.3 molB) 0.0464 molC) 21.5 molD) 0.00381 molE) 2.90 mol

Q: How many moles of gas are in a gas sample occupying 0.738L at 135mmHg and 30ºC?A) 190 molB) 4.01 molC) 40.5 molD) 0.00527 molE) 0.000433 mol

Q: What is the pressure of a 59.6-L gas sample containing 3.01mol of gas at 44.9ºC? (R=0.0821L atm/(K mol), 1 atm=760 torr)A) 1.41 x102mmHgB) 1.73 x10-3mmHgC) 1.32 mmHgD) 1.00 x103mmHgE) 5.77 x102mmHg

Q: Which of the following graphs does notcorrectly describe the ideal gas law?A) B) They all correctly represent the ideal gas law.C) D) E)

Q: The volume of 1 mol of nitrogen A) is lower than that of 1mol ammonia at high pressures. B) is decreased by decreasing the pressure of the gas. C) has the value of 22.4 L at 0C and 1.00 atm. D) is decreased by increasing its kinetic energy. E) is increased by decreasing the temperature.

Q: For an ideal gas, which of the following statements is true? A) V is inversely proportional to n at constant P and T. B) P is inversely proportional to T at constant n and V. C) P is inversely proportional to n at constant V and T. D) P is inversely proportional to V at constant n and T. E) V is inversely proportional to T at constant n and P.

Q: The behavior of PH3(g) is most likely to approach ideal behavior atA) 1.0 atm and 100ºC.B) 0.10 atm and -100ºC.C) 10 atm and 100ºC.D) 0.10 atm and 100ºC.E) 1.0 atm and 0ºC.

Q: Which conditions of P, T, and n, respectively, are most ideal? A) low P, low T, low n B) high P, low T, high n C) low P, high T, high n D) low P, high T, low n E) high P, high T, high n

Q: A gas occupies a volume of 2.00L at 860mmHg and 30.0ºC. Which of the following mathematical expressions will yield its volume at STP?A) B) C) D) E)

Q: What volume of gaseous water, H2O, has the same moles of gas as 10.0L of xenon gas at the same temperature and pressure?A) 40.0 LB) 2.50 LC) 10.0 LD) 3.33 LE) 30.0 L

Q: What volume of methane gas, CH4, has the same number of atoms as 6.00L of krypton gas at the same temperature and pressure?A) 36.0 LB) 1.00 LC) 6.00 LD) 1.20 LE) 30.0 L

Q: Which of the following statements, concerning equal volumes of the gases dinitrogen monoxide, N2O, and propane, C3H8, at the same temperature and pressure, is not correct?A) The moles of N2O and C3H8 are equal.B) They have the same density.C) They have the same number of molecules.D) They have the same number of atoms.E) They have the same absolute temperature.

Q: A 1.00-L bulb contains a sample of O2 at 25ºC and 1.00 atm pressure. A second 1.00-L bulb contains a sample of CH4 at 25ºC and 1.00 atm pressure. What is the ratio of the number of molecules of methane to the number of molecules of oxygen in each of the containers?A) 2:5B) C) 5:2D) E) 1:1

Q: Equal volumes of propane, C3H8, and carbon monoxide, CO, at the same temperature and pressure have the sameA) chemical properties.B) number of atoms.C) average molecular speed.D) density.E) number of molecules.

Q: A fixed amount of gas in a rigid container is heated from 100ºC to 700ºC. Which of the following responses best describes what will happen to the pressure of the gas?A) The pressure will increase by a factor greater than 7.B) The pressure will increase by a factor of 7.C) The pressure will increase by a factor less than 7.D) The pressure will decrease by a factor of 7.E) The pressure will remain the same.

Q: A 22.4-L sample of nitrogen at 3.65atm and 22ºC is simultaneously expanded to 57.4L and heated to 38ºC. What is the new pressure of the gas?A) 2.46 atmB) 1.50 atmC) 204 atmD) 334 atmE) 1.35 atm

Q: A fixed amount of gas in a rigid container is heated from 300 to 900K. Which of the following responses best describes what will happen to the pressure of the gas? A) The pressure will increase by a factor of 3. B) The pressure will increase by a factor less than 3. C) The pressure will increase by a factor greater than 3. D) The pressure will decrease by a factor of 3. E) The pressure will remain the same.

Q: A given mass of gas occupies a volume of 4.00 L at 60ºC and 550 mmHg. Which of the following mathematical expressions will yield its temperature at 3.00L and 775mmHg?A) B) C) D) E)

Q: Which of the following concerning the ideal gas law is/are true? 1) Pressure is directly proportional to volume when temperature and moles of gas are held constant. 2) Pressure is directly proportional to moles of gas when temperature and volume are held constant. 3) Volume is inversely proportional to temperature when the pressure and moles of gas are held constant. A) 1 only B) 2 only C) 3 only D) 1 and 2 only E) 2 and 3 only

Q: The pressure of 4.2L of nitrogen gas in a flexible container is decreased to one-half its original pressure, and its absolute temperature is increased to double the original temperature. The volume is now A) 2.1 L. B) 4.2 L. C) 8 L. D) 17 L. E) 1.1 L.

Q: A rigid container is charged with a gas to a pressure of 760mmHg at 20.0ºC and tightly sealed. If the temperature of the gas increases by 40.0ºC what is the new pressure?A) 1520 mmHgB) 669 mmHgC) 656 mmHgD) 864 mmHgE) 1140 mmHg

Q: A gas occupying a volume of 1.50 L exerts a pressure of 700 mmHg at 200ºC. Which mathematical expression gives the correct pressure at 6.00L and 400ºC?A) B) C) D) E)

Q: A gas occupies a volume of 2.75 L at 350 mmHg and 200ºC. Which mathematical expression gives the correct volume at 550mmHg and 450ºC?A) B) C) D) E)

Q: A flexible container is charged with a certain volume of gas at 318.3 K. Under conditions of constant pressure and moles of gas, how does the volume of the gas change when the temperature is decreased by a factor of four?A) The volume decreases by a factor of four.B) The volume decreases by a factor of two.C) The volume remains the same.D) The volume increases by a factor of three.E) The volume increases by a factor of two.

Q: A flexible container is charged with 51.00L of gas at 368 K. Under conditions of constant pressure and moles of gas, what is the volume of the gas when the temperature is tripled?A) 153 LB) 17.0 LC) 0.0588 LD) 51 LE) 0.850 L

Q: The volume of a sample of gas measured at 55.0ºC and 1.00 atm pressure is 8.00L. What must the final temperature be in order for the gas to have a final volume of 9.00L at 1.00 atm pressure?A) 96.0CB) 61.9CC) -211.1CD) 48.9CE) 18.6C

Q: Which of the following is a correct statement of Charles's law, ? A) The volume of a gas varies proportionally with the pressure. B) The volume of a gas sample varies directly with the absolute temperature. C) All gas samples of the same volume at STP contain the same number of atoms. D) The pressure of a gas sample varies inversely with the volume. E) All gas samples of the same volume at STP contain the same number of molecules.

Q: The following volume-temperature plots were made at different values of constant pressure while the number of moles of gas in each experiment remained the same. Which plot represents measurements at the highest pressure? A) B B) C C) A D) They are all at the same pressure. E) D

Q: Absolute zero is the point at whichA) a straight-line graph of V versus T (ºC) intersects the origin.B) a straight-line graph of 1/Vversus Pat constant Tintersects the origin.C) gaseous helium liquefies.D) a straight-line graph of Vversus 1/Pat constant Tintersects the origin.E) a straight-line graph of V versus T (K) intersects the origin.

Q: When the valve between the 2.00-L bulb, in which the gas pressure is 3.00atm, and the 3.00-L bulb, in which the gas pressure is 2.50atm, is opened, what will be the final pressure in the two bulbs? Assume the temperature remains constant. A) 2.70 atm B) 5.50 atm C) 2.83 atm D) 2.80 atm E) 2.67 atm

Q: A sample of methane, CH4, occupies a volume of 170.0mL at 25ºC and exerts a pressure of 965.0mmHg. If the volume of the gas is allowed to expand to 720.0mL at 298 K, what will be the pressure of the gas?A) 4090 mmHgB) 2720 mmHgC) 227.8 mmHgD) 0.008823 mmHgE) 550.0 mmHg

Q: A 2.00-L glass soda bottle filled only with air is tightly capped at 24ºC and 744.0mmHg. If the bottle is placed in water at 75ºC, what is the pressure in the bottle?A) 238 mmHgB) 872 mmHgC) 2330 mmHgD) 635 mmHgE) 383 mmHg

Q: A flexible vessel contains 53L of gas where the pressure is 1.6atm. What will the volume be when the pressure is 0.61atm, the temperature remaining constant? A) 0.007 L B) 20 L C) 53 L D) 0.042 L E) 139 L

Q: A flexible vessel is filled to a certain pressure with 12.00 L of gas. Under conditions of constant temperature and moles of gas, how does the volume of the gas change when the pressure of the gas is decreased by a factor of three? A) The volume increases by a factor of three. B) The volume increases by a factor of two. C) The volume increases by a factor of four. D) The volume decreases by a factor of two. E) The volume decreases by a factor of four.

Q: A flexible vessel contains 32.00L of gas at a pressure of 1.59atm. Under conditions of constant temperature and moles of gas, what is the volume of the gas when the pressure of the vessel is decreased by a factor of three? A) 96.1 L B) 10.7 L C) 0.0104 L D) 32 L E) 4.80 L

Q: A flexible vessel contains 47L of gas where the pressure is 1.3atm. What will the volume be when the pressure is 0.85atm, the temperature remaining constant?A) 0.014 LB) 31 LC) 47 LD) 0.046 LE) 72 L

Q: The pressure of a certain gas is measured to be 5.159x103Pa. What is this pressure expressed in units of mmHg?A) 6.699 x10-5mmHgB) 3.921 x106mmHgC) 2.584 x10-2mmHgD) 38.70 mmHgE) 1.493 x104mmHg

Q: The pressure of a certain gas is measured to be 360.6mmHg. What is this pressure expressed in units of pascals?A) 4.683 x10-6PaB) 2.136 x105PaC) 2.080 x10-5PaD) 3.654 x107PaE) 4.808 x104Pa

Q: A particular gas exerts a pressure of 7.54x104Pa. What is this pressure in units of atmospheres?A) 0.744 atmB) 7.44 x109atmC) 0.764 atmD) 0.754 atmE) 7.64 x109atm

Q: A particular gas exerts a pressure of 2.62x104Pa. What is this pressure in units of bar?A) 2.62 x109barB) 0.262 barC) 34.5 barD) 2.59 x104barE) 2.65 x104bar

Q: A particular gas exerts a pressure of 2.27atm. What is this pressure in units of bar?A) 1.73 x103barB) 2.27 x105barC) 2.30 barD) 2.24 barE) 2.99 x10-3bar

Q: A particular gas exerts a pressure of 4.79atm. What is this pressure in units of mmHg?A) 4.73 mmHgB) 3.64 x103mmHgC) 4.85 mmHgD) 6.30 x10-3mmHgE) 3.69 x103mmHg

Q: A particular gas exerts a pressure of 3.43bar. What is this pressure in units of atmospheres?A) 3.48 atmB) 2.57 x103atmC) 2.64 x103atmD) 3.39 atmE) 3.43 atm

Q: A particular gas exerts a pressure of 2.79bar. What is this pressure in units of pascals?A) 2.75 x105PaB) 2.79 x10-5PaC) 2.79 x105PaD) 2.83 x105PaE) 2.75 x10-5Pa

Q: A particular gas exerts a pressure of 785mmHg. What is this pressure in units of atmospheres?A) 5.89 x105atmB) 6.05 x105atmC) 775 atmD) 1.05 atmE) 1.03 atm

Q: A particular gas exerts a pressure of 621mmHg. What is this pressure in units of bar?A) 4.66 x105barB) 4.78 x105barC) 629 barD) 0.806 barE) 0.828 bar

Q: It is possible to make a barometer using a liquid other than mercury. What would be the height (in meters) of a column of water at a pressure of 0.390 atm, given that 0.390 atm is equal to a 0.296 m column of mercury and the densities of mercury and water are 13.5 g/cm3 and 1.00 g/cm3, respectively.A) 4.00 mB) 0.250 mC) 0.0220 mD) 0.296 mE) 3.37 m