Ideal Gas Laws

the partial pressure s of CH4 N2 and O2 in a sample of gas mixture were found to be 135mmHg,508mmHg, and 571 mmHg respectively. What is the mole fraction of nitrofen gas in the mixture?

0.0418

zinc is added to hydrochloric acid to generate hydrogen gas, which is collected over water at 20degrees C. The volumeof gas sample collected is 1.7L and its total pressure is 0.810atm. The vapor pressure of water at 20degrees C is 18 torr. the number of moles of hydrogen gas present in sample is

0.056mol

A glass column filled with mercury and inverted in a pool of mercury . The mercury column stabilizes at a height of 729mm above the pool of mercury. What is the pressure of the atmosphere?

0.959atm

Given the reaction: N2 + 3H2 -> 2NH3, you mix 1 mole each of nitrogen and hydrogen gases under the same conditions in a container fitted witha piston. What is the ration of volumes of the container, Vfinal/Vinitial?

1. BCA table 2. LR 3. Vf/Vi=nf/ni ans: 0.67

at 1000C and 10torr, the density of a certain element in the gaseous state is 2.9x10^-3g/L. The element is

1. M = dRT/P ans: Na

a 142 mL sample of gas is collected over water at 22C and 753 torr. What is the volume of the dry gas at STP?(the vapor pressure of water is 22C=20torr)

1. P1V1/T1 = P2V2/T2 ans: none of these

a sample of nitrous oxide, N2O, occupies 16,500 mL at STP. What is the mass of the sample?

1. PV = nRT 2. mol to g ans: 32.4g

a sample of oxygen gas has a volume of 1.72L at 27C and 800.0 torr. how many oxygen molecules does the sample contain?

1. PV = nRT 2. mol to molecules ans: 4.43 x 10^22 molecules

Oxygen gas, generated by the reaction 2KClO3 (s) --> 2KCl (s) + 3O2 (g) is collected over water at 27 C in a 1.55 L vessel at a total pressure of 1.00 atm. (The vapor pressure of H2O at 27 C is 26.0 torr.) How many moles of KClO3 were consumed in the reaction?

1. Pgas=Ptotal-Ph2o 2. PV=nRT -- n(o2) 3. moles of KClO3 ans: 0.0405moles

into a 2.22L container at 25 C are placed 1.23moles of oxygen gas and 3.20moles of solid carbon (C). If the carbon and oxygen react completely to form carbon monoxide gas, what is the final pressure in the container at 25 C?

1. balance equation 2. BCA table 3. LR 4. PV=nRT ans: 27.1atm

consider the reaction between ethane, C2H6, and oxygen gas to produce carbon dioxide and water. What volume of carbon dioxide gas is produced at STP from the reaction of 4.00L of ethane and 7.00L of oxygen?

1. balance equation 2. limiting reactant 3.BCA table ans: 4.00L CO2

a gaseous mixture containing 1.5mol Ar and 3.5mol CO2 has a total pressure of 7.3atm. What is the partial pressure of CO2?

1. calculate mole fraction 2. calculate partial pressure with Ptotal*Xi ans:5.1atm

a 3.54gram sample of a certain diatomic gas occupies a volume of 3.30L at 1.00atm and a temperature of 45degrees C. Identify this gas.

1. find 'n' 2.calculate 'M' ans:N2

a 7.94g piece of solid CO2(dry ice) is allowed to sublime in a balloon. the final volume of the balloon is 1.00L at 301K. What is the pressure of the gas?

1. g to mol 2. PV =nRT ans: 4.46atm

what volume does 40.5g of nitrogen gas occupy at STP

1. g to mol 2. PV=nRT ans: 32.4L

Mercury vapor contains Hg atoms. What is the volume of 201 g of mercury vapor at 822 K and 0.512 atm?

1. g to mol 2. PV=nRT ans:132L

what volume is occupied by 21.0g of methane(CH4) at 27degrees C and 1.25atm?

1. g to mol 2. PV=nRT ans:25.8L

You have 41.6 g of O2 gas in a container with twice the volume as one with CO2 gas. The pressure and temperature of both containers are the same. Calculate the mass of carbon dioxide gas you have in the container.

1. g to mol 2. V1/n1=V2/n2 3. mol to g ans: 28.6g

given the equation 2KClO3 -->2KCl =3O2, a 3.00g sample of KClO3 is decomposed and the oxygen at 24C and 0.717 atm is collected. What volume of oxygen gas will be collected assuming 100% yield?

1. g to mol 2. find mol of O2 using equation 3. PV = nRT ans: 1.25 x 10 ^2 mL

a 3.31 g sample of lead(II)nitrate, Pb(NO3)2, molar mass = 331g/mol, is heated in an evacuated cylinder with a volume 2.37L. The salt decomposes when heated, according to the equation: 2Pb(NO3)2 --> 2PbO + 4NO2 + O2 assuming complete decomposition, what is the pressure in the cylinder after decomposition and cooling to temperature of 300K?

1. g to mol 2. find number of moles of NO2 and O2 3. PV = nRT ans: 0.260atm

calcium hydride combines with water according to the equation: CaH2 + 2H2O -> Ca(OH)2 + 2H2. Beginning with 84.0g of CaH2 and 42.0g of H2o, what volume of H2 will be produced at 273K and a pressure of 1327torr?

1. identify LR 2. PV =nRT ans: 29.9L

what volume of water vapor measure at STP is produced by the combustion of 6.27g of natural gas according to the equation: CH4 +2O2 -> CO2 + 2H2O

1. n=m/M 2. PV=nRT ans: 17.5L

When 0.72 g of a liquid is vaporized at 110°C and 0.967 atm, the gas occupies a volume of 0.559 L. The empirical formula of the gas is CH2. What is the molecular formula of the gas?

1.d=n/V 2.M =dRT/P 3. find empirical mass for CH2 4. scale factor = molar mass/empirical mass 5. multiply empirical formula by scale factor ans: C3H6

consider a sample of a gas in a container on a comfortable spring day. the celsius temperature suddenly doubles, and you transfer the gas to a container twice the volume of the first container. if the original pressure was 12atm, what is a good estimate for the new pressure?

1/2P = 2V T increase= P increase ans: 6.4atm

which of the following represent the greatest pressure

11.4psi

you are holding two balloons, an orange balloon and a blue balloon. The orange ballon is filled with Ne gas and the blue ballon is filled with Ar gas. The orange balloon has twice the volume of the blue balloon which of the following best represent the mass ration of Ne:Ar in the balloons?

1:1

a physics experiment is conducted at a pressure of 14.4kPa. What is this pressure in mmHg?

1atm=101.3kPa=760mmHg ans: 108mmHg

For a gas, which two variables are directly proportional to each other if all other conditions remain constant?

2 and 3 only

For an ideal gas law which pairs of variables are inversely proportional to each other if all other factors remain constant?

2 only

What volume of carbon dioxide measured at STP will be formed by the reaction of 1.47 mol of oxygen with 0.900 mol of ethyl alcohol, CH3CH2OH?

22.0L

zinc is added to hydrochloric acid to generate hydrogen gas, which is collected over water at 20degrees C. The volumeof gas sample collected is 1.7L and its total pressure is 0.810atm. The vapor pressure of water at 20degrees C is 18 torr. the partial pressure of hrdrogen gas in the sample is

598torr

a mixture is prepared from 15.0L od ammonia and 15.0L of chlorine measure at the same conditiosn of temperature and pressure. A chemical reation occures according to the equation: 2NH3 + 3Cl2 -> N2 + 6HCl. When the reaction is complete, what is the volume of each gas in order mentioned in the equation?

5L, 0L, 5L, 30L

four identical 1.0L flasks contain the gases He, Cl2, CH4, and NH3, each at 0degrees C and 1atm pressure. Assuming the gases are ideal in nature, which gas are the collisions elastic?

all collisions in all the gases are elastic

Which of the following statements is false?

all gases have the same density at STP

three 1.00L flasks A,B and C at 25degrees C and 725 torr contain the gases CH4,CO2, and C2H6 respectively. In which flask is there 0.039mol of gas?

all the flasks contain 0.039mol of gas

charles' law states that

The volume of a fixed amount of gas is directly proportional to its temperature in Kelvin at constant pressure

body temperature is about 309K. On a cold day, what volume of air at 276K must a person with a lung capacity of 2.2L breathe in to fill the lungs?

V1/T1 =V2/T2 ans:1.97L

Which of the following statements is true concerning ideal gases?

a gas exerts pressure as a result of the collisions of the gas molecules with the walls of the container

four identical 1.0L flasks contain the gases He, Cl2, CH4, and NH3, each at 0degrees C and 1atm pressure. Assuming the gases are ideal in nature, which gas has the greater number of molecules ?

ans: all gases have the same number of moles

all of the following are postulates of the kinetic molecular theory of gases except

at a constant temperature, each molecule has the same kinetic energy

four identical 1.0L flasks contain the gases He, Cl2, CH4, and NH3, each at 0degrees C and 1atm pressure. Assuming the gases are ideal in nature, which gas has smalled avg KE?

avg KE only depends on temp ans: all gases have the same average kinetic energy

four identical 1.0L flasks contain the gases He, Cl2, CH4, and NH3, each at 0degrees C and 1atm pressure. Assuming the gases are ideal in nature, which gas do the molecules have the highest avg velocity?

avg velocity depends on temp and molar mass greater temp=greater volume greater molar mass = smaller volume ans: He

the temperature of a gas sample is doubled from 20degrees C to 40degrees C. What would happen to the average kinetic energy of the gas molecules?

it would increase

which conditions of p, T and n, respectively, are most ideal?

low P, high T, low n

gases generally have

low density

three 1.00L flasks A,B and C at 25degrees C and 725 torr contain the gases CH4,CO2, and C2H6 respectively. in which single flask do the molecules have the greatest mass, the greater average velocity and the highest kinetic energy?

no one flask has all these

Given a cylinder of fixed volume filled with 1 mol of argon gas, which of the following is correct? (Assume all gases obey the ideal gas law)

none of the above

the temperature of a specific amount of gas in a sealed container changes from 20degrees C to 40degrees C. If the volume remains constant, the pressure will change from 755mmHg to

p1/t1 =p2/t2 ans: 807mmHg

the valve between the 2.00L bulb, in which the gas pressure is 1.80atm, and the 3.00L bulb, in which the gas pressure is 3.00atm, is opened. What is the final pressure in the two bulbs, the temperature remaining constant?

p1v1+p2v2=p3v3 ans:2.52atm

a gas sample is heated from -20degrees C to 57degrees C and the volume is increase from 2.00L to 4.50L. If the initial pressure is 0.140atm, what is the final pressure?

p1v1/t1 =p2v2/t2 ans:0.0811atm

a sample of helium gas occupies 14.7L at 23degrees C and 0.956atm. What volume does it occupy at 40degrees C and 1.20at?

p1v1/t1 =p2v2/t2 ans:12.4L

The SI unit of pressure is the

pascal

which of the following would have a higher rate of effusion thean C2H2?

smaller M=greater effusion rate ans: CH4

You have a certain mass of helium gas (He) in a rigid steel container. You add the same mass of neon gas (Ne) to this container. Which of the following best describes what happens?

the pressure in the container increases but does not double

graham's law states that

the rates of effusion of gases are inversely proportional to the square roots of their molar masses

daltons law of partial pressure states

the total pressure of a mixture of gases is equal to the sum of the pressure of all the gases in the mixture

boyle's law states

the volume of a fixed amount of gas is inversely proportional to its pressure at constant temperature

a baloon has a volume of 2.32liters ar 24.0degrees C. The balloon is heated to 48degrees C. Calculate the new volume of the balloon

v1/t1=v2/t2 ans:2.51L

which statement is inconsistent with kinetic energy of ideal gas?

when two gas molecules collide, they both gain kinetic energy

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

greater 'n'=greater 'v' ans: H2

four identical 1.0L flasks contain the gases He, Cl2, CH4, and NH3, each at 0degrees C and 1atm pressure. Assuming the gases are ideal in nature, which gas has the highest density?

greater M = greater d ans: Cl2

which of the following pollutant gases is not produced directly in a combustion engine?

O3

order the following gases in increasing rate of effusion

Cl2first to(<) CH4last

the density of oxygen gas at 25degrees C and 0.850atm is

M = dRT/P ans: 1.11g/L

the mass of 1.12liters of gas Y at STP is found to be 6.23g. The molar mass of gas Y is

M = dRT/P ans: 125g/mol

If a 17.90 g sample of a gas occupies 10.0 L at STP, what is the molar mass of the gas ?

M = dRT/P ans: 40.1g/mol

argon has a density of 1.78g/L at STP. How many of the following gases have a density at STP greater than that of argon?

M=dRT/P ans: 2

the mass of 1.12liters of gas Y at STP is found to be 6.23g. The density of gas Y is

d=m/V ans: 5.56g/L

Real gases are those that

deviate from ideal behavior

four identical 1.0L flasks contain the gases He, Cl2, CH4, and NH3, each at 0degrees C and 1atm pressure. Assuming the gases are ideal in nature, which gas are the molecules diatomic?

diatomic=consistes of two atoms in total ans: Cl2

Avogadro's law states

equal amounts of gases occupy the same volume at constant STP