Question 1

How many molecules of N2 are in a 300.0 mL container at 780 mm Hg and 135°C?

Accepted Answer

A) 5.26 × 1021 molecules 
B) 5.54 × 1021 molecules 
C) 1.59 × 1022 molecules 
D) 1.67 × 1022 molecules 
A) 5.26 × 1021 molecules 
B) 5.54 × 1021 molecules 
C) 1.59 × 1022 molecules 
D) 1.67 × 1022 molecules

Question 2

If CO2 and NH3 are allowed to effuse through a porous membrane under identical conditions,the rate of effusion for NH3 will be ________ times that of CO2.

Accepted Answer

A) 0.39 
B) 0.62 
C) 1.6 
D) 2.6 
A) 0.39 
B) 0.62 
C) 1.6 
D) 2.6

Question 3

If NO2 and NH3 are allowed to effuse through a porous membrane under identical conditions,the rate of effusion for NH3 will be ________ times that of CO2.

Accepted Answer

A) 0.37 
B) 0.61 
C) 1.6 
D) 2.7 
A) 0.37 
B) 0.61 
C) 1.6 
D) 2.7

Question 4

In the diagram below,nitrogen molecules are represented by unshaded spheres,oxygen molecules by gray spheres,and chlorine molecules by black spheres.  
-If the total pressure in the container is 100.mm Hg,what is the partial pressure of chlorine?

Accepted Answer

A) 10.0 mm Hg 
B) 20.0 mm Hg 
C) 30.0 mm Hg 
D) 50.0 mm Hg 
A) 10.0 mm Hg 
B) 20.0 mm Hg 
C) 30.0 mm Hg 
D) 50.0 mm Hg

Question 5

A gas bottle contains 0.800 mol of gas at 730 mm Hg pressure.If the final pressure is 1.15 atm,how many moles of gas were added to the bottle?

Accepted Answer

A) 0.0012 mol 
B) 0.158 mol 
C) 0.958 mol 
D) 0.0668 mol 
A) 0.0012 mol 
B) 0.158 mol 
C) 0.958 mol 
D) 0.0668 mol

Question 6

Some assumptions from the kinetic molecular theory are listed below.Which one is most frequently cited to explain compressibility of a gas?

Accepted Answer

A) The average kinetic energy of gas particles is proportional to the Kelvin temperature. 
B) Collisions of gas particles are elastic and total kinetic energy of the gas is constant. 
C) A gas consist of tiny particles moving in random straight line motion. 
D) The volume of the particles is negligible compared to the volume of the gas. 
A) The average kinetic energy of gas particles is proportional to the Kelvin temperature. 
B) Collisions of gas particles are elastic and total kinetic energy of the gas is constant. 
C) A gas consist of tiny particles moving in random straight line motion. 
D) The volume of the particles is negligible compared to the volume of the gas.

Question 7

One mole of gas at 25°C has a ________ volume than one mole of gas at standard temperature.

Accepted Answer

The answer of One mole of gas at 25°C has...

Question 8

The region of the atmosphere that is closest to the earth's surface is the ________.

Accepted Answer

The answer of The region of the atmosphere that is...

Question 9

Which of the following gases has the lowest average speed at 25°C?

Accepted Answer

A) C2H6 
B) H2Se  
C) PH3   
D) F2 
A) C2H6 
B) H2Se  
C) PH3   
D) F2

Question 10

How many liters of oxygen are needed to exactly react with 55.6 g of methane at STP? CH4(g)+ 2 O2(g)→ CO2(g)+ 2 H2O(l)

Accepted Answer

A) 19.5 L 
B) 39.0 L 
C) 156 L 
D) 77.8 L 
A) 19.5 L 
B) 39.0 L 
C) 156 L 
D) 77.8 L

Question 11

Assume that you have a sample of gas in a cylinder with a moveable piston,as shown in diagram (1).The initial pressure,number of moles,and temperature of the gas are noted on the diagram.Which diagram (2)-(4)most closely represents the result of doubling the pressure and number of moles of gas while keeping the temperature constant?

Accepted Answer

A) diagram (2) 
B) diagram (3) 
C) diagram (4) 
A) diagram (2) 
B) diagram (3) 
C) diagram (4)

Question 12

-What is the pressure (in mm Hg)of the gas inside the above apparatus if the outside pressure,Patm,is 740 mm Hg and the difference in mercury levels,Δh,is 30 mm Hg?

Accepted Answer

A) 30 mm Hg 
B) 710 mm Hg 
C) 740 mm Hg 
D) 770 mm Hg 
A) 30 mm Hg 
B) 710 mm Hg 
C) 740 mm Hg 
D) 770 mm Hg

Question 13

Which of the following is equivalent to 1 atm pressure?

Accepted Answer

A) 1.101325 bar 
B) 1.00 bar 
C) 20 psi 
D) 740 mm Hg 
A) 1.101325 bar 
B) 1.00 bar 
C) 20 psi 
D) 740 mm Hg

Question 14

You have two samples of the same gas in the same size container,with the same pressure.The gas in the first container has a Kelvin temperature four times that of the gas in the other container.The ratio of the number of moles of gas in the first container compared to that in the second is

Accepted Answer

A) 1:1. 
B) 1:2. 
C) 1:4. 
D) 4:1. 
A) 1:1. 
B) 1:2. 
C) 1:4. 
D) 4:1.

Question 15

A glass tube has one end in a dish of mercury and the other end closed by a stopcock.The distance from the surface of the mercury to the bottom of the stopcock is 800 mm,as indicated by the meter stick shown in the drawing below.The apparatus is at 20°C,and the mercury level in the tube is the same as that in the dish.  
-Which drawing best shows the approximate level of the mercury in the tube when a vacuum pump is connected to the top of the tube,the stopcock opened,the tube is evacuated,the stopcock is closed,and the pump is removed?

Accepted Answer

A) drawing (1) 
B) drawing (2) 
C) drawing (3) 
D) drawing (4) 
A) drawing (1) 
B) drawing (2) 
C) drawing (3) 
D) drawing (4)

Question 16

Three identical flasks contain three different gases at standard temperature and pressure.Flask A contains   flask B contains SO2,and flask C contains He. Which flask contains the largest number of molecules?

Accepted Answer

A) flask A 
B) flask B 
C) flask C 
D) All contain same number of molecules. 
A) flask A 
B) flask B 
C) flask C 
D) All contain same number of molecules.

Question 17

If the Earth's ozone (O3)layer has a total volume of 1.00 × 1020 km3,a partial pressure of 1.6 × 10-9 atm,and an average temperature of 230 K,how many ozone molecules are in the Earth's ozone layer?

Accepted Answer

A) 2.3 × 1035 molecules 
B) 5.1 × 1035 molecules 
C) 2.3 × 1045 molecules 
D) 5.1 × 1045 molecules 
A) 2.3 × 1035 molecules 
B) 5.1 × 1035 molecules 
C) 2.3 × 1045 molecules 
D) 5.1 × 1045 molecules

Question 18

A basketball is inflated to a pressure of 1.80 atm in a 23.0°C garage.What is the pressure of the basketball outside where the temperature is -2.00°C?

Accepted Answer

A) 1.65 atm 
B) 1.70 atm 
C) 1.90 atm 
D) 1.97 atm 
A) 1.65 atm 
B) 1.70 atm 
C) 1.90 atm 
D) 1.97 atm

Question 19

According to the kinetic molecular theory of gases,at 290 K the average kinetic energy of O2 is ________ the average kinetic energy of NO2.

Accepted Answer

Question 20

A gas occupies 22.4 L at STP and 9.85 L at 100.°C and 2.00 atm pressure.How many moles of gas did the system gain or lose?

Accepted Answer

A) 1.36 moles gained 
B) 1.64 moles gained 
C) 0.644 moles lost 
D) 0.356 moles lost 
A) 1.36 moles gained 
B) 1.64 moles gained 
C) 0.644 moles lost 
D) 0.356 moles lost

Exam 10: Gases: Their Properties and Behavior

How many molecules of N2 are in a 300.0 mL container at 780 mm Hg and 135°C?

If CO2 and NH3 are allowed to effuse through a porous membrane under identical conditions,the rate of effusion for NH3 will be ________ times that of CO2.

If NO2 and NH3 are allowed to effuse through a porous membrane under identical conditions,the rate of effusion for NH3 will be ________ times that of CO2.

In the diagram below,nitrogen molecules are represented by unshaded spheres,oxygen molecules by gray spheres,and chlorine molecules by black spheres. -If the total pressure in the container is 100.mm Hg,what is the partial pressure of chlorine?

A gas bottle contains 0.800 mol of gas at 730 mm Hg pressure.If the final pressure is 1.15 atm,how many moles of gas were added to the bottle?

Some assumptions from the kinetic molecular theory are listed below.Which one is most frequently cited to explain compressibility of a gas?

One mole of gas at 25°C has a ________ volume than one mole of gas at standard temperature.

The region of the atmosphere that is closest to the earth's surface is the ________.

Which of the following gases has the lowest average speed at 25°C?

How many liters of oxygen are needed to exactly react with 55.6 g of methane at STP? CH4(g)+ 2 O2(g)→ CO2(g)+ 2 H2O(l)

-What is the pressure (in mm Hg)of the gas inside the above apparatus if the outside pressure,Patm,is 740 mm Hg and the difference in mercury levels,Δh,is 30 mm Hg?

Which of the following is equivalent to 1 atm pressure?

You have two samples of the same gas in the same size container,with the same pressure.The gas in the first container has a Kelvin temperature four times that of the gas in the other container.The ratio of the number of moles of gas in the first container compared to that in the second is

Three identical flasks contain three different gases at standard temperature and pressure.Flask A contains flask B contains SO2,and flask C contains He. Which flask contains the largest number of molecules?

If the Earth's ozone (O3)layer has a total volume of 1.00 × 1020 km3,a partial pressure of 1.6 × 10-9 atm,and an average temperature of 230 K,how many ozone molecules are in the Earth's ozone layer?

A basketball is inflated to a pressure of 1.80 atm in a 23.0°C garage.What is the pressure of the basketball outside where the temperature is -2.00°C?

According to the kinetic molecular theory of gases,at 290 K the average kinetic energy of O2 is ________ the average kinetic energy of NO2.

A gas occupies 22.4 L at STP and 9.85 L at 100.°C and 2.00 atm pressure.How many moles of gas did the system gain or lose?

Chemical Tools: Experimentation and Measurement

Atoms, molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Periodicity and the Electronic Structure of Atoms

Ionic Compounds: Periodic Trends and Bonding

Covalent Bonding and Electron-Dot Structures

Covalent Compounds: Bonding Theories and Molecular Structure

Thermochemistry: Chemical Energy

Liquids, solids, and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

The Main-Group Elements

Connections to Organic and Biological Chemistry

Filters

How many molecules of N₂ are in a 300.0 mL container at 780 mm Hg and 135°C?

If CO₂ and NH₃ are allowed to effuse through a porous membrane under identical conditions,the rate of effusion for NH₃ will be ________ times that of CO₂.

If NO₂ and NH₃ are allowed to effuse through a porous membrane under identical conditions,the rate of effusion for NH₃ will be ________ times that of CO₂.

How many liters of oxygen are needed to exactly react with 55.6 g of methane at STP? CH₄(g)+ 2 O₂(g)→ CO₂(g)+ 2 H₂O(l)

-What is the pressure (in mm Hg)of the gas inside the above apparatus if the outside pressure,P_atm,is 740 mm Hg and the difference in mercury levels,Δh,is 30 mm Hg?

Three identical flasks contain three different gases at standard temperature and pressure.Flask A contains flask B contains SO₂,and flask C contains He_. Which flask contains the largest number of molecules?

If the Earth's ozone (O₃)layer has a total volume of 1.00 × 10²⁰ km³,a partial pressure of 1.6 × 10^-9 atm,and an average temperature of 230 K,how many ozone molecules are in the Earth's ozone layer?

According to the kinetic molecular theory of gases,at 290 K the average kinetic energy of O₂ is ________ the average kinetic energy of NO₂.