Question 1

To what temperature must a balloon,initially at 25 °C and 2.00 L,be heated to have a volume of 6.00 L?

Accepted Answer

A) 993 K 
B) 403 K 
C) 75 K 
D) 655 K 
E) 894 K 
A) 993 K 
B) 403 K 
C) 75 K 
D) 655 K 
E) 894 K

Question 2

Determine the mass of water formed when 12.5 L NH3 (at 298 K and 1.50 bar)is reacted with 18.9 L of O2 (at 323 K and 1.1 bar). 
4NH3(g)+ 5O2(g)→ 4NO(g)+ 6H2O(g)

Accepted Answer

A) 16.7 g H2O 
B) 20.7 g H2O 
C) 37.7 g H2O 
D) 13.8 g H2O 
E) 27.9 g H2O 
A) 16.7 g H2O 
B) 20.7 g H2O 
C) 37.7 g H2O 
D) 13.8 g H2O 
E) 27.9 g H2O

Question 3

If 0.240 mol of He were added to a balloon,how large would the balloon grow? Atmospheric pressure is 0.9871 bar and the ambient temperature is 23.2 °C.

Accepted Answer

A) 5.99 L 
B) 6.54 L 
C) 3.73 L 
D) 6.49 L 
E) 7.28 L 
A) 5.99 L 
B) 6.54 L 
C) 3.73 L 
D) 6.49 L 
E) 7.28 L

Question 4

What is the temperature if krypton has a root mean square velocity of 348 m $s ^ { - 1 }$ ?

Accepted Answer

A) 800°C 
B) 791°C 
C) 134°C 
D) 604°C 
E) 596°C 
A) 800°C 
B) 791°C 
C) 134°C 
D) 604°C 
E) 596°C

Question 5

A gas mixture contains CO,Ar,and H2.What is the total pressure of the mixture if the mole fraction of H2 is 0.35 and the pressure of H2 is 0.58 bar?

Accepted Answer

A) 1.7 bar 
B) 0.20 bar 
C) 0.49 bar 
D) 0.60 bar 
E) 2.1 bar 
A) 1.7 bar 
B) 0.20 bar 
C) 0.49 bar 
D) 0.60 bar 
E) 2.1 bar

Question 6

Which of the gases in the graph below has the largest molar mass?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) There is not enough information to determine the answer. 
A) A 
B) B 
C) C 
D) D 
E) There is not enough information to determine the answer.

Question 7

Convert 123.80 kPa to bar.

Accepted Answer

A) 1.222 bar 
B) 1.087 bar 
C) 0.8078 bar 
D) 0.9186 bar 
E) 1.238 bar 
A) 1.222 bar 
B) 1.087 bar 
C) 0.8078 bar 
D) 0.9186 bar 
E) 1.238 bar

Question 8

At what temperature does argon have a root mean square velocity of 492 m s-1?

Accepted Answer

A) 321 K 
B) 291 K 
C) 340 K 
D) 388 K 
E) 409 K 
A) 321 K 
B) 291 K 
C) 340 K 
D) 388 K 
E) 409 K

Question 9

Name the major gas in dry air.

Accepted Answer

nitrogen o

Question 10

A gas mixture consists of N2,O2,and Ne,where the mole fraction of N2 is 0.55 and the mole fraction of Ne is 0.25.If the mixture is at STP in a 5.0 L container,how many molecules of O2 are present?

Accepted Answer

A) 4.5 × 1022 molecules O2 
B) 2.7 × 1022 molecules O2 
C) 3.7 × 1023 molecules O2 
D) 1.1 × 1023 molecules O2 
E) 9.3 × 1024 molecules O2 
A) 4.5 × 1022 molecules O2 
B) 2.7 × 1022 molecules O2 
C) 3.7 × 1023 molecules O2 
D) 1.1 × 1023 molecules O2 
E) 9.3 × 1024 molecules O2

Question 11

Why does the rate of effusion increase with a decrease in the molar mass?

Accepted Answer

The rate of effusion depends o

Question 12

Determine the total volume of all gases (at STP)formed when 50.0 mL of TNT C3H5(NO3)3,d = 1.60 g mL-1,molar mass = 227.10 g mol-1)reacts according to the following reaction: 
4C3H5(NO3)3(l)→ 6N2(g)+ O2(g)+ 12CO2(g)+ 10H2O(g)

Accepted Answer

A) 4.93 L 
B) 58.0 L 
C) 29.6 L 
D) 448 L 
E) 175 L 
A) 4.93 L 
B) 58.0 L 
C) 29.6 L 
D) 448 L 
E) 175 L

Question 13

The mole fraction of oxygen in dry air near sea level is 0.20948.The concentration of oxygen is ________ molecules per litre,assuming an atmospheric pressure of 0.985 bar and a temperature of 29.5 °C.

Accepted Answer

A) 6.23 
B) 0.00819 
C) 4.94 × 1021 
D) 3.75 × 1024 
E) 5.07 × 1022 
A) 6.23 
B) 0.00819 
C) 4.94 × 1021 
D) 3.75 × 1024 
E) 5.07 × 1022

Question 14

Determine the density of CO2 gas at STP.

Accepted Answer

A) 1.94 g $\mathrm { L } ^ { - 1 }$ 
B) 1.80 g $\mathrm { L } ^ { - 1 }$ 
C) 2.24 g $\mathrm { L } ^ { - 1 }$ 
D) 4.46 g $\mathrm { L } ^ { - 1 }$ 
E) 5.10 g $\mathrm { L } ^ { - 1 }$ 
A) 1.94 g $\mathrm { L } ^ { - 1 }$ 
B) 1.80 g $\mathrm { L } ^ { - 1 }$ 
C) 2.24 g $\mathrm { L } ^ { - 1 }$ 
D) 4.46 g $\mathrm { L } ^ { - 1 }$ 
E) 5.10 g $\mathrm { L } ^ { - 1 }$

Question 15

Why doesn't Dalton's law of partial pressures depend on the identity of the gases present?

Accepted Answer

It is assumed that all gas particles are

Question 16

Which of the following gases has the highest average speed at 400 K?

Accepted Answer

A) N2 
B) O2   
C) F2 
D) Cl2 
A) N2 
B) O2   
C) F2 
D) Cl2

Question 17

A sample of N2 effuses in 255 s.How long will the same size sample of Cl2 take to effuse?

Accepted Answer

A) 406 s 
B) 247 s 
C) 645 s 
D) 155 s 
E) 388 s 
A) 406 s 
B) 247 s 
C) 645 s 
D) 155 s 
E) 388 s

Question 18

A sample of gas initially has a volume of 859 mL at 565 K and 2.20 bar.What pressure will the sample have if the volume changes to 268 mL while the temperature is increased to 815 K?

Accepted Answer

A) 10.2 bar 
B) 9.83 bar 
C) 15.3 bar 
D) 6.53 bar 
E) 1.05 bar 
A) 10.2 bar 
B) 9.83 bar 
C) 15.3 bar 
D) 6.53 bar 
E) 1.05 bar

Question 19

How many molecules of XeF6 are formed from 12.9 L of F2 (at 298 K and 2.635 bar)according to the following reaction? Assume that there is excess Xe. Xe(g)+ 3F2(g)→ XeF6(g)

Accepted Answer

A) 1.21 × 1023 molecules XeF6 
B) 8.25 × 1023 molecules XeF6 
C) 2.75 × 1023 molecules XeF6 
D) 7.29 × 1023 molecules XeF6 
E) 1.37 × 1023 molecules XeF6 
A) 1.21 × 1023 molecules XeF6 
B) 8.25 × 1023 molecules XeF6 
C) 2.75 × 1023 molecules XeF6 
D) 7.29 × 1023 molecules XeF6 
E) 1.37 × 1023 molecules XeF6

Question 20

If 0.3781 g of a gas with a molecular weight of 18.015 g $\mathrm { mol } ^ { - 1 }$ is in a ridged 5.00 L container at 384 K,calculate the final pressure.Assume ideal behaviour.

Accepted Answer

A) 0.682 bar 
B) 0.109 bar 
C) 0.0867 bar 
D) 0.132 bar 
E) 0.0963 bar 
A) 0.682 bar 
B) 0.109 bar 
C) 0.0867 bar 
D) 0.132 bar 
E) 0.0963 bar

Exam 5: Gases

To what temperature must a balloon,initially at 25 °C and 2.00 L,be heated to have a volume of 6.00 L?

Determine the mass of water formed when 12.5 L NH3 (at 298 K and 1.50 bar)is reacted with 18.9 L of O2 (at 323 K and 1.1 bar). 4NH3(g)+ 5O2(g)→ 4NO(g)+ 6H2O(g)

If 0.240 mol of He were added to a balloon,how large would the balloon grow? Atmospheric pressure is 0.9871 bar and the ambient temperature is 23.2 °C.

What is the temperature if krypton has a root mean square velocity of 348 m s−1s ^ { - 1 }s−1 ?

A gas mixture contains CO,Ar,and H2.What is the total pressure of the mixture if the mole fraction of H2 is 0.35 and the pressure of H2 is 0.58 bar?

Which of the gases in the graph below has the largest molar mass?

Convert 123.80 kPa to bar.

At what temperature does argon have a root mean square velocity of 492 m s-1?

Name the major gas in dry air.

A gas mixture consists of N2,O2,and Ne,where the mole fraction of N2 is 0.55 and the mole fraction of Ne is 0.25.If the mixture is at STP in a 5.0 L container,how many molecules of O2 are present?

Why does the rate of effusion increase with a decrease in the molar mass?

Determine the total volume of all gases (at STP)formed when 50.0 mL of TNT C3H5(NO3)3,d = 1.60 g mL-1,molar mass = 227.10 g mol-1)reacts according to the following reaction: 4C3H5(NO3)3(l)→ 6N2(g)+ O2(g)+ 12CO2(g)+ 10H2O(g)

The mole fraction of oxygen in dry air near sea level is 0.20948.The concentration of oxygen is ________ molecules per litre,assuming an atmospheric pressure of 0.985 bar and a temperature of 29.5 °C.

Determine the density of CO2 gas at STP.

Why doesn't Dalton's law of partial pressures depend on the identity of the gases present?

Which of the following gases has the highest average speed at 400 K?

A sample of N2 effuses in 255 s.How long will the same size sample of Cl2 take to effuse?

A sample of gas initially has a volume of 859 mL at 565 K and 2.20 bar.What pressure will the sample have if the volume changes to 268 mL while the temperature is increased to 815 K?

How many molecules of XeF6 are formed from 12.9 L of F2 (at 298 K and 2.635 bar)according to the following reaction? Assume that there is excess Xe. Xe(g)+ 3F2(g)→ XeF6(g)

If 0.3781 g of a gas with a molecular weight of 18.015 g mol−1\mathrm { mol } ^ { - 1 }mol−1 is in a ridged 5.00 L container at 384 K,calculate the final pressure.Assume ideal behaviour.

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Filters

Determine the mass of water formed when 12.5 L NH₃ (at 298 K and 1.50 bar)is reacted with 18.9 L of O₂ (at 323 K and 1.1 bar). 4NH₃(g)+ 5O₂(g)→ 4NO(g)+ 6H₂O(g)

What is the temperature if krypton has a root mean square velocity of 348 m $s ^ { - 1 }$ ?

A gas mixture contains CO,Ar,and H₂.What is the total pressure of the mixture if the mole fraction of H₂ is 0.35 and the pressure of H₂ is 0.58 bar?

At what temperature does argon have a root mean square velocity of 492 m s^-1?

A gas mixture consists of N₂,O₂,and Ne,where the mole fraction of N₂ is 0.55 and the mole fraction of Ne is 0.25.If the mixture is at STP in a 5.0 L container,how many molecules of O₂ are present?

Determine the total volume of all gases (at STP)formed when 50.0 mL of TNT C₃H₅(NO₃)₃,d = 1.60 g mL^-1,molar mass = 227.10 g mol^-1)reacts according to the following reaction: 4C₃H₅(NO₃)₃(l)→ 6N₂(g)+ O₂(g)+ 12CO₂(g)+ 10H₂O(g)

Determine the density of CO₂ gas at STP.

A sample of N₂ effuses in 255 s.How long will the same size sample of Cl₂ take to effuse?

How many molecules of XeF₆are formed from 12.9 L of F₂ (at 298 K and 2.635 bar)according to the following reaction? Assume that there is excess Xe. Xe(g)+ 3F₂(g)→ XeF₆(g)

If 0.3781 g of a gas with a molecular weight of 18.015 g $\mathrm { mol } ^ { - 1 }$ is in a ridged 5.00 L container at 384 K,calculate the final pressure.Assume ideal behaviour.