Chem

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A particular gas exerts a pressure of 3.08 atm. What is this pressure in units of bar?

4.05 × 10^-3 bar 3.03 bar 3.12 bar 2.34 × 10^3 bar

​A particular gas exerts a pressure of 4.35 × 10^4 Pa. What is this pressure in units of bar?

4.35 × 10^9 bar ​4.41 × 10^4 bar ​57.2 bar ​4.29 × 10^4 bar

The density of O2 gas at 3 °C and 1.87 atm is

41.9 g/L. 243 g/L. 0.379 g/L. 2.64 g/L.

Calculate the ratio of the effusion rates of N2 and N2O.

1.25

A 22.4 L high pressure reaction vessel is charged with 0.4290 mol of iron powder and 1.58 atm of oxygen gas at standard temperature. On heating, the iron and oxygen react according to the balanced reaction below. 4 Fe(s) + 3 O2(g) → 2 Fe2O3(s) After the reaction vessel returns to standard temperature, and assuming the reaction goes to completion, what pressure of oxygen remains?

1.25 atm

A mixture of krypton and argon gases, in a 8.65-L flask at 22.0 oC, contains 15.3 g of krypton and 15.6 g of argon. What is the total pressure in the flask?

1.60 atm 1.09 atm 0.511 atm 0.428 atm

When the valve between the 2.00-L bulb, in which the gas pressure is 1.00 atm, and the 3.00-L bulb, in which the gas pressure is 3.50 atm, is opened, what will be the final pressure in the two bulbs? Assume the temperature remains constant.

1.83 atm

A physics experiment is conducted at a pressure of 14.0 kPa. What is this pressure in mmHg?

105 mm Hg

A rigid container is charged with a gas to a pressure of 740 mmHg at 40.0 °C and tightly sealed. If the temperature of the gas increases by 80.0 °C what is the new pressure?

1110 mmHg 1480 mmHg 929 mmHg

How many moles of gas are in a gas sample occupying 0.612 L at 138 mmHg and 36 °C?

0.00438 mol

A sample of methane, CH4, occupies a volume of 182.0 mL at 25 °C and exerts a pressure of 1190.0 mmHg. If the volume of the gas is allowed to expand to 620.0 mL at 298 K, what will be the pressure of the gas?

0.01164 mm Hg 349.3 mm Hg 4160 mm Hg 4050 mm Hg

A sample of xenon gas occupies a volume of 7.52 L at 53 oC and 0.643 atm. If it is desired to decrease the volume of the gas sample to 4.60 L, while decreasing its pressure to 0.466 atm, the temperature of the gas sample at the new volume and pressure must be

0.0426 C -128 C -63.4 C -204 C

Given the equation: 2 KClO3(s) à 2 KCl(s) + 3 O2(g) A 3.00-g sample of KClO3 (Molar Mass = 122.55 g/mol) is decomposed and the oxygen is collected at 24.0 °C and 0.991 atm. What volume of oxygen gas will be collected, assuming 100% yield?

0.730 L 0.904 L 0.559 L 0.602 L

A mixture of gases consists of CH4 at a partial pressure of 143 mm Hg, N2 at a partial pressure of 469 mm Hg, and O2 at a partial pressure of 563 mm Hg. Calculate the mole fraction of oxygen in this mixture.

0.741 20.1 0.399 0.479

What is the density (in g/L) of methane at 25 °C and 1.2 atm of pressure? The value of R = 0.082057 L· atm/mol · K.

0.785

A sample of oxygen is collected over water at a total pressure of 504.1 mm Hg at 30 °C. The vapor pressure of water at 30 °C is 31.8 mm Hg. The partial pressure of the O2 is

0.9010 atm. 0.6214 atm. 1.110 atm. 0.7051 atm.

Convert 699 torr to 1) atm, 2) mmHg- 3) kPa.

0.920 699 93.2

Calcium nitrate will react with ammonium chloride at slightly elevated temperatures, as represented in the equation below. Ca(NO3)2(s) + 2 NH4Cl(s) → 2 N2O(g) + CaCl2(s) + 4 H2O(g) What is the maximum volume of N2O at STP that could be produced using a 5.80-mol sample of each reactant?

129 L

A helium-filled weather balloon has a volume of 652 L at 18 oC and 756 mm Hg. It is released and rises to an altitude of 6.55 km, where the pressure is 398 mm Hg and the temperature is -22 oC. The volume of the balloon at this altitude is

1440 L 1260 L 1510 L 1220 L

A mixture of argon and carbon dioxide gases, at a total pressure of 942 mm Hg, contains 5.75 g of argon and 11.4 g of carbon dioxide. What is the partial pressure of carbon dioxide in the mixture?

158 mm Hg 337 mm Hg 165 mm Hg 605 mm Hg

An automobile tire is inflated to a pressure of 31.4 psi. What is the pressure in torr? Hint: 1 atm = 760 torr = 14.7 psi

1620 torr

A 22.6-L sample of nitrogen at 4.05 atm and 25 °C is simultaneously expanded to 52.2 L and heated to 38 °C. What is the new pressure of the gas?

192 atm 1.68 atm 2.67 atm 1.83 atm

The following equation represents the partial combustion of methane, CH4. 2 CH4(g) + 3 O2(g) → 2 CO(g) + 4 H2O(g) At constant temperature and pressure, what is the maximum volume of carbon monoxide that can be obtained from 6.25 × 102 L of methane and 3.13 × 102 L of oxygen? Group of answer choices

2.08 × 10^2 L

If a certain volume of methane, CH4, effuses through a small hole at a rate of 5.5 x 10^-6 mol/hr, the rate of effusion for the same volume of helium through the hole under the same conditions will be

2.2 * 10^-5 mol/hr. 1.1 * 10^-5 mol/hr. 1.4 * 10^-6 mol/hr.

A 9.70-g piece of solid CO2 (Molar Mass = 44.01 g/mol) is allowed to sublime in a balloon. The final volume of the balloon is 1.00 L at 298 K. What is the pressure of the gas inside the balloon

2.37 × 102 atm 5.39 atm 2.52 atm none of these

What is the volume occupi ed by a mixture of 0.515 mol of N2 and 0.515 mol of O2 gases at 0.84 atm and 48.7 °C?

2.45 L

A student inflates a balloon to a volume of 972 mL by filling it with argon gas at a pressure of 1.50 atm and a temperature of 15.8 oC. How many grams of argon gas are needed?

2.46 g 2.81 g

What is the pressure in a 2.0 L container at 27 °C that contains 2.0 g O2 and 4.0 g N2?

2.5 atm 4.4 atm 5.0 atm 1.3 atm

What volume of H2O (g) measured at STP is produced by the combustion of 3.71 g of natural gas (CH4) according to the following equation? CH4 + 2O2 --> CO2 + 2H2O

2.59 L 11 L 10.3 L

A particular gas exerts a pressure of 2.98 bar. What is this pressure in units of atmospheres?

2.94 atm

A vessel with a volume of 19.0 L contains 2.80 g of nitrogen gas, 0.403 g of hydrogen gas, and 79.9 g of argon gas. At 25 °C, what is the pressure in the vessel?

2.96 atm

In a mixture of helium and chlorine, occupying a volume of 18.2 L at 831.4 mm Hg and 48.0 oC, it is found that the partial pressure of helium is 527 mm Hg. What is the total mass of the sample?

21.5 g

The partial pressures of CH4, N2, and O2 in a sample of gas were found to be 123 mm Hg, 446 mm Hg, and 713 mm Hg, respectively. What is the mole fraction of nitrogen?

22.3 0.556 0.938 0.348

The density of a gas is 1.25 g/L at STP. What is its molar mass?

28.0 g/mol 21.0 g/mol 37.6 g/mol

A neon gas sample occupies a volume of 3.62 L at 21.6 oC and 0.875atm. If the pressure remains constant, at what temperature will the volume of the gas be 3.45 L?

281k

What is the ratio of the average speed of He molecules to that of CH4 molecules at 298 K?

2:1

What is the total volume of gases produced at 819 K and 1.00 atm pressure when 320 g of ammonium nitrite undergoes the following decomposition reaction? NH4NO2(s) → N2(g) + 2 H2O(g)

3.36 * 10^2L 22.4 L 6.72 * 10^1L 1.01 * 10^3L

A vessel with a volume of 14.8 L contains 2.80 g of nitrogen gas, 0.403 g of hydrogen gas, and 79.9 g of argon gas. At 25 °C, what is the pressure in the vessel?

3.80 atm

A 100 mL sample of oxygen gas is collected over water at 26 °C and at a pressure of 756 torr. Given that the vapor pressure of water at 26 °C is 25 torr, how many moles of dry oxygen are present?

3.9 × 10−3 mol

A 17.8-g mixture of oxygen and argon is found to occupy a volume of 11.9 L when measured at 754.1 mm Hg and 36.3 oC. What is the partial pressure of argon in this mixture?

377 mm Hg 618 mm Hg 592 mm Hg

What is the partial pressure of oxygen in a container that contains 6.22 mol of oxygen, 4.35 mol of nitrogen, and 2.39 mol of carbon dioxide when the total pressure is 817 mm Hg? Group of answer choices

392 mm Hg

What is the root mean square (rms) speed of neon gas at 127 °C?

396 m/s 406 m/s 12.2 m/s 703 m/s

What is the ratio of the average rate of effusion of CH4HBr(g) at 400 K?

7:4

What is the pressure of a 91.8-L gas sample containing 4.12 mol of gas at 25.9 °C? (R = 0.082057 L · atm/K · mol, 1 atm = 760 mmHg)

8.37 × 102 mmHg

A flexible container is charged with 10.00 L of gas at 350 Κ. Under conditions of constant pressure and moles of gas, what is the temperature of the gas when the volume is decreased by a factor of four? Group of answer choices

87.4 K

A sample of a gas at 2.31 atm of pressure occupies 4.10 L. What will the volume be if the pressure is changed to 1.02 atm at constant temperature?

9.28 L 4.65 L 18.6 L 1.81 L

Calculate the root-mean-square velocity for the O2 molecules in a sample of O2 gas at 32.7 °C. (R = 8.3145 J/K⋅mol)

9.296 × 10^26 m/s 488.1 m/s 15.44 m/s

A student reads a barometer in the laboratory and finds that the prevailing atmospheric pressure to be 747 mmHg. What is the pressure in kPa?

99.6 kPa

What volume of carbon dioxide is produced when 189 L of butane ( C4H10) react with excess oxygen, according to the following reaction? (all gases are at the same temperature and pressure) 2 C4H10(g) + 13 O2(g) à 8 CO2(g) + 10 H2O(g)

993 L 756 L 526 L

You are holding four identical balloons each containing 10.0 g of a different gas. The balloon containing which gas is the largest balloon?

Ar CH4 CS2 All balloons will have the same volume.

The following information will be used to answer question 13-16. Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 25°C and 1 atm pressure. Which gas will have the greatest kinetic energy?

Cl2 All gases will have the same kinetic energy. CH4 NH3

The following information will be used Heto answer question 13-16. Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 25°C and 1 atm pressure. Which flask contains the greatest number of moles of gas?

Cl2 NH3 CH4

The following information will be used to answer question 13-16. Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 25°C and 1 atm pressure. If the flasks are opened simultaneously, which gas will travel the farthest?

He CH4 Cl2 NH3

Which of the following is not a postulate of the kinetic molecular theory?

The forces of attraction and repulsion between the particles are insignificant. The moving particles undergo perfectly elastic collisions with the walls of the container. Gas particles have most of their mass concentrated in the nucleus of the atom.

A fixed amount of gas in a rigid container is heated from 300 K to 600 K. Which of the following responses best describes what will happen to the pressure of the gas?

The pressure will remain the same. The pressure will increase by a factor of 2. The pressure will increase by a factor less than 2. The pressure will increase by a factor greater

A flexible container is charged with a certain volume of gas at 298.8 Κ. Under conditions of constant pressure and moles of gas, how does the temperature of the gas change when the volume is decreased by a factor of three?

The temperature decreases by a factor of three. The temperature remains the same. The temperature increases by a factor of two.

A flexible vessel is filled to a certain pressure with 87.00 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 two?

The volume increases by a factor of two.

Which of the following statements is incorrect regarding a 192-g sample of gaseous sulfur dioxide at 0 °C and 760 mm Hg pressure?

The volume of the gas is 67.2 L. The molar mass of the gas is 64 g/mol. The density of the gas is 2.86 g/L. There are 3 × 6.02 × 1023 atoms of oxygen present.

Under what conditions do real gases most closely approximate the behavior of ideal gases?

low pressure and high temperature

What volume is occupied by 19.8 g of methane (CH4) at 27 °C and 2.34 atm?

not enough data to calculate 2.08*10^2 L 13.0 L

​A particular gas exerts a pressure of 2.61 × 104 Pa. What is this pressure in units of atmospheres?

​0.257 atm

​A particular gas exerts a pressure of 4.7 bar. What is this pressure in units of pascals?

​4.7 × 10^5 Pa

The volume of a sample of gas measured at 65.0 °C and 1.00 atm pressure is 8.00 L. What must the final temperature be in order for the gas to have a final volume of 3.00 L at 1.00 atm pressure?

-146.3 °C

Ammonia gas is synthesized according to the balanced equation below. N2(g) + 3 H2(g) → 2 NH3(g) If 1.55 L N2 react with 4.92 L H2, what is the theoretical yield (in liters) of NH3? Assume that the volumes of reactants and products are measured at the same temperature and pressure.

6.42 L 3.10 L 3.28 L 4.93 L

The following equation represents the oxidation of ammonia, NH3. 4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(g) At the same temperature and pressure, what is the maximum volume of nitrogen monoxide that can be obtained from 6.98 × 102 L of ammonia and 6.98 × 102 L of oxygen?

6.98 × 10^2 L 3.1 × 10^2 L 1.4 × 10^3 L 1.57 × 10^3 L

What is the molar mass of a gas if 10 g occupies 8.2 L at 380 torr and 27 °C?

60 g/mol 30 g/mol 90 g/mol none of these

The molar mass of an unknown gas was measured by an effusion experiment. It was found that the unknown gas effused at a rate of 2.8 × 10−6 mol/hr, whereas nitrogen gas effused at a rate of 4.1 × 10−6 mol/hr. The molar mass of the gas is

60 g/mol. 13 g/mol. 34 g/mol.

​The pressure of a certain gas is measured to be 8.372 × 103 Pa. What is this pressure expressed in units of mm Hg?

62.79 mm Hg

If 375.4 mL of nitrogen gas, measured at 840.6 mmHg and 59.9 oC, reacts with excess iodine according to the following reaction, what mass of nitrogen triiodide is produced? N2(g) + 3 I2(s) → 2 NI3(s)

66.6 g 11.9 g 5.99 g

A flexible vessel contains 80.00 L of gas at a pressure of 2.52 atm. Under conditions of constant temperature and moles of gas, what is the pressure of the gas when the volume of the vessel is decreased by a factor of three?

7.560 atm 0.132 atm 0.839 atm 2.52 atm

An excess of sodium hydroxide is treated with 2.9 L of dry hydrogen chloride gas measured at STP. What is the mass of sodium chloride is formed?

7.6 g

A gas occupying a volume of 1.50 L exerts a pressure of 700 mmHg at 200 °C. Which mathematical expression gives the correct pressure at 5.00 L and 600 °C?

700mmHg * (1.5L/5.00L) * (873K/473K)

What is the root mean square (rms) speed of neon gas at 127 °C?

703 m/s

A small amount wet of hydrogen gas (H2) can be prepared by the reaction of zinc with excess hydrochloric acid and trapping the gas produced in an inverted tube initially filled with water. If the total pressure of the gas in the collection tube is 744.3 mm Hg at 21 °C, what is the partial pressure of the hydrogen? The vapor pressure of water is 18.7 mm Hg.

725.6 mm Hg

The following information will be used to answer question 13-16. Four identical 1.0-L flasks contain the gases He, Cl2, CH4, and NH3, each at 25°C and 1 atm pressure. Which gas has the highest density?

All gases will have the same density. CH4 NH3 Cl2

What can you say about the pressures of the gases in the boxes below, if both gas samples are at the same temperature?

Both samples have the same pressure. Not enough information to tell which has the highest pressure. The sample in Container A has the highest pressure.


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