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Name ……………………………………… Unit 9 Notes: Gas Laws Period ______ Skills: 1. Gases and Entropy 2. Distinguish between Ideal and Real gases 3. Understand KMT and Avogadro’s Law 4. Identify and Solve Boyle’s Law Problems 5. Identify and Solve Charles’ Law Problems 6. Use Combined Gas Law Equation 7. Diffusion and Effusion 8. Dalton’s Law of Partial Pressures 9. Vapor Pressure and Table H 10. Molar Density and Molar Quantities 11. Convert Between Moles and Liters Unit 9: Vocabulary: Complete throughout unit. Due on test day! Word Definition Entropy Ideal Gas Kinetic Molecular Theory Pressure Closed System Constant Pressure Diffusion Partial Pressure Molar Volume Vapor Pressure Combined Gas Law Direct Relationship

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Page 1: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Name ……………………………………… Unit 9 Notes: Gas Laws Period ______

Skills:

1. Gases and Entropy 2. Distinguish between Ideal and Real

gases 3. Understand KMT and Avogadro’s Law 4. Identify and Solve Boyle’s Law Problems 5. Identify and Solve Charles’ Law

Problems

6. Use Combined Gas Law Equation 7. Diffusion and Effusion 8. Dalton’s Law of Partial Pressures 9. Vapor Pressure and Table H 10. Molar Density and Molar Quantities 11. Convert Between Moles and Liters

Unit 9: Vocabulary: Complete throughout unit. Due on test day!

Word Definition

Entropy

Ideal Gas

Kinetic Molecular Theory

Pressure

Closed System

Constant Pressure

Diffusion

Partial Pressure

Molar Volume

Vapor Pressure

Combined Gas Law

Direct Relationship

Page 2: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Skill #1: Gases and Entropy Entropy: _________________________________________________________

Increases when…1)___________________

2) Something dissolves (becomes aqueous)

*____________________

Comparing States of Matter: solids, liquids, & gases

• Particle arrangement: _____________________________

__________________________ • Intermolecular forces of

attraction: ___

• Shape: ________

• Volume: _______

• Entropy: _____

• Particle arrangement: ____________________________

_________________________ • Intermolecular forces of

attraction: ______

• Shape: ___________ __________________

• Volume: _________

• Entropy: ______

• Particle arrangement: _______________________________

___________________________ • Intermolecular forces of

attraction: _____ • Shape: _____________

___________________ • Volume: ______________

___________________ * COMPRESSIBLE

• Entropy: _______

*Gases are most affected by changes in temperature, pressure, and volume.

Units You May Run Into

Temperature (Kelvin!!) Pressure Volume

K = °C + 273 (Table T)

Ex: What is 33.7°C equal to in Kelvins?

kPa and atm

1 atm = 101.3 kPa

Ex: What is the pressure in kPa of 0.92 atm?

L to mL à use King Henry 1 mL = 1 cm3

Ex: What is 0.845 L equal to in cm3?

Page 3: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Skill 2: Distinguish Between IDEAL vs. REAL Gases and Conditions

1. Gases behave most ideally under conditions of _____ _______ and ____ ______

BECAUSE…….

a. particles are moving _____AND b. particles are ______ _______

2. Gases deviate (stray) from ideal under conditions of ______ __________ and

________ ________________. BECAUSE……

1. particles are moving _____ AND 2. particles are ______ ________

3. H2 and _____ are nearly ideal gases because they are the smallest and have the weakest

intermolecular forces Skill 3: Understand Kinetic Molecular Theory and Avogadro’s Law

Ideal Gas

- ________________........!

- Follows the gas laws

- Particles are ______ attracted to each other

- Particles have ____ volume

(negligible)

Real Gas

- ________________________

- Do not follow gas laws exactly

- Particles DO attract each other (have some intermolecular forces of attraction)

- Particles DO have some volume…atomic radii

Less chance of gas particles attracting each other

Gas particles will attract each other

Four Assumptions: (Memorize These L)

1. Gas particles are in ________, random, straight-line motion.

2. When gas particles collide, energy is __________ from one particle to another

(_________ collisions).

3. Gas particles have no attraction to each other (no IMF).

4. Individual gas particles have no _________ (negligible).

Ideal gases are like an ideal good boyfriend or girlfriend….

___________________ and not a lot of ______________________.

Page 4: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Kinetic Molecular Theory (KMT): Model that explains ________________________ of an ideal gas!

Avogadro’s Law:

Practice:

1. Which one has more gas particles? _________________________________________ 2. Which one will behave the most ideally? _____________________________________ 3. Which one has the most atoms? Explain. _____________________________________

1. According to the kinetic molecular

theory, which assumption is correct? (1) Gas particles strongly attract each

other. (2) Gas particles travel in curved paths. (3) The volume of gas particles prevents

random motion. (4) Energy may be transferred between

colliding particles.

2. Which of these changes produces the greatest increase in entropy? (1) CaCO3(s) → CaO(s) + CO2(g) (2) H2O(g) → H2O(l) (3) 2 Mg(s) + O2(g) → 2 MgO(s) (4) CO2(g) → CO2(s)

3. Helium is most likely to behave as an ideal gas when it is under

(1) high pressure and high temperature (3) low pressure and high temperature (2) high pressure and low temperature (4) low pressure and low temperature

4. Under which conditions of temperature and pressure does oxygen gas behave least like an ideal gas?

(1) low temperature and low pressure (3) high temperature and low pressure (2) low temperature and high pressure (4) high temperature and high pressure

“EQUAL _________ of different gases at the SAME temperature and pressure contain EQUAL _____________ ____ ______________”

Ex: 12 mL of CO2 gas at STP has the same number of molecules as 12 mL of O2 gas at STP.

(Same conditions, same volumes, same # of particles)

Define A MOLAR VOLUME: ___________liters

CO2

100 kpa

5.0L

800K

H2

100 kpa

5.0L

800K

Ar

100 kpa

5.0L

800K

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Name_______________________________ Bell Ringer

1. Which sample at STP has the same number of molecules as 5 liters of NO2(g) at STP? (1) 5 grams of H2(g) (3) 5 moles of O2(g) (2) 5 liters of CH4(g) (4) 5 x 1023 molecules of CO2(g)

2. At the same temperature and pressure, 1.0 liter of CO (g) and 1.0 liter of CO2 (g) have (1) Equal volumes and the same number of molecules (2) Equal masses and the same number of molecules (3) Different masses and a different number of molecules (4) Different volumes and a different number of molecules

3. At the same temperature and pressure, which sample contains the same number of moles of particles as 1 liter of O2 (g)? (1) 1 L Ne (g) (2) 0.5 L SO2 (g) (3) 2 L O2 (g) (4) 1 L of H2O (l)

NAME__________ Bell Ringer Ideal vs Real

1. What are the two reasons why real gases do not behave exactly like ideal gases?

• Real gases have _______________________. • Real gas particles have __________________.

2. Which of these changes produces the greatest increase in entropy?

(1) CaCO3(s) → CaO(s) + CO2(g) (3) H2O(g) → H2O(l) (2) 2 Mg(s) + O2(g) → 2 MgO(s) (4) CO2(g) → CO2(s)

NAME__________ Bell Ringer Ideal vs Real

1. What are the two reasons why real gases do not behave exactly like ideal gases?

• Real gases have _______________________. • Real gas particles have __________________.

2. Which of these changes produces the greatest increase in entropy?

(1) CaCO3(s) → CaO(s) + CO2(g) (3) H2O(g) → H2O(l) (2) 2 Mg(s) + O2(g) → 2 MgO(s) (4) CO2(g) → CO2(s)

NAME__________ Bell Ringer Ideal vs Real

1. What are the two reasons why real gases do not behave exactly like ideal gases?

• Real gases have _______________________. • Real gas particles have __________________.

2. Which of these changes produces the greatest increase in entropy?

(1) CaCO3(s) → CaO(s) + CO2(g) (3) H2O(g) → H2O(l) (2) 2 Mg(s) + O2(g) → 2 MgO(s) (4) CO2(g) → CO2(s)

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Skill 4: Identify and Solve Boyle’s Law Problems Boyle’s Law: As the pressure on a gas _________, the volume of the gas ____________. This is an _______________ relationship.

`

1. A balloon is filled with 73 L of air at 1.3 atm pressure. What pressure is needed to change to

volume to 43 L?

2. A sample of Helium gas is compressed from 4.0 L to 2.5 L at a constant temperature. If the

pressure of the gas in the 4.0 L volume is 210 kPa, what will the pressure be at 2.5 L?

3. A gas sample contained in a cylinder equipped with a moveable piston occupied 300.0 mL at a pressure of 2.00 atm. What would be the final pressure if the volume were increased to 500.0 mL at constant temperature? (1.2atm)

4. A balloon that contains 1.50 L of air at 1.00 atm is taken underwater to a depth at which the pressure is 3.00 atm. Calculate the new volume of the balloon. Assume that the temperature remains constant. (0.5L)

P1V1 = P2V2

Example: A balloon is filled with 25 L of air at 1.0 atm pressure. If the pressure is changed to 1.5 atm what is the new volume?

P1= ______ V1= ______ P2= ______ V2= ______

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NAME_______________ Boyle Bell Ringer

1. A sample of krypton gas occupies 75.0 mL at 0.400 atm. If the temperature remained

constant, what volume would the krypton occupy at 4.00 atm? (7.5mL) NAME_______________ Boyle Bell Ringer

1. A sample of krypton gas occupies 75.0 mL at 0.400 atm. If the temperature remained

constant, what volume would the krypton occupy at 4.00 atm? (7.5mL) NAME_______________ Boyle Bell Ringer

1. A sample of krypton gas occupies 75.0 mL at 0.400 atm. If the temperature remained

constant, what volume would the krypton occupy at 4.00 atm? (7.5mL) NAME_______________ Boyle Bell Ringer

1. A sample of krypton gas occupies 75.0 mL at 0.400 atm. If the temperature remained

constant, what volume would the krypton occupy at 4.00 atm? (7.5mL) NAME_______________ Boyle Bell Ringer

1. A sample of krypton gas occupies 75.0 mL at 0.400 atm. If the temperature remained

constant, what volume would the krypton occupy at 4.00 atm? (7.5mL)

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Name_________________ Boyle’s Graphing!

Use the sample data in the table below to plot and graph and answer the questions associated with Boyle’s Law. Pressure is the y variable and volume is the x variable.

Trial Pressure (kPa) Volume (mL)

1 100 kPa 40 mL

2 50 kPa 80 mL

3 200 kPa 20 mL

4 400 kPa 10 mL

5 25 kPa 160 mL

Questions:

1. What does the data show happens to the pressure when the volume is double?

2. What does the data show happens to the pressure when the volume is halved?

3. Does the data and the shape of your plot support that pressure and volume are inversely related? How?

4. Based upon your graph, what would you expect the pressure to be if the volume was increased to 600 mL?

5. Based upon your graph, what would you expect the volume to be if the pressure is changed to 60 kPa.

Page 9: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Skill 5: Identify and Solve Charles’ Law Problems Charles’ Law: As the Temperature of a substance ____________________, the volume also _____________________. This is a _____________________ graphical relationship.

1. A sample of nitrogen occupies a volume of 250 mL at 25°C. What volume will it occupy at 95°C?

2. Oxygen gas is at a temperature of 40°C when it occupies a volume of 2.3 liters. To what temperature should it be raised to occupy a volume of 6.5 liters?

3. Several balloons are inflated with helium to a volume of 0.75 L at 27°C. One of the balloons was found several hours later, the temperature had dropped to 22°C. What would be the volume of the balloon when found, if no helium has escaped?

4. A weather balloon is filled to the volume of 150.0 L on a day when the temperature is 10°C. If no gases escaped, what would be the volume of the weather balloon after it rises to an altitude where the temperature is -8°C?

𝑽𝟏𝑻𝟏

=𝑽𝟐𝑻𝟐

Example: A sample of gas at 40.0 °C occupies a volume of 2.32 L. If the temperature is raised to 75.0 °C what will the new volume be?

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NAME_______________ Charles’ Bell Ringer A gas occupies a volume of 100.0 mL at 27°C and 630 kpa. At what temperature, in degrees Celsius, would a volume of 50 mL be at 630 kpa?

NAME_______________ Charles’ Bell Ringer A gas occupies a volume of 100.0 mL at 27°C and 630 kpa. At what temperature, in degrees Celsius, would a volume of 50 mL be at 630 kpa?

NAME_______________ Charles’ Bell Ringer A gas occupies a volume of 100.0 mL at 27°C and 630 kpa. At what temperature, in degrees Celsius, would a volume of 50 mL be at 630 kpa?

NAME_______________ Charles’ Bell Ringer A gas occupies a volume of 100.0 mL at 27°C and 630 kpa. At what temperature, in degrees Celsius, would a volume of 50 mL be at 630 kpa?

Page 11: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Name______________________ Graphing Charles’ Law

Use the sample data in the table below to plot and graph and answer the questions associated with Charles’ Law. Graph volume (L) as the y variable and temperature (K) as the x variable. Remember…temperatures must be converted to Kelvin values! (K=C+273)

Questions:

1. What does the data show happens to the volume as the temperature is doubled?

_____________________________________________________________________

2. What does the data show happens to the volume as the temperature is halved?

_____________________________________________________________________

3. According to the data and the plot, what is the relationship (direct or inverse) between volume and temperature as described by Charles’ Law? _____________

4. Based upon your graph, what would you expect the volume to be if the temperature is raised to 1000K?____________

Calculations:

1. A sample of gas has a volume of 33.2 mL and a pressure of 105 kPa. What will the new pressure be if the volume expands to 75 mL?

2. A balloon inflated in an air-conditioned room at 27 C has a volume of 4.0 L. The balloon is taken outside where the temperature raises up to 57 C. What is the new volume of the balloon?

Trial Volume (L)

Temperature (C)

Temperature (K)

1 1.0 L 27 C

2 1.33 L 127 C

3 2.0 L 327 C

4 2.33 L 427 C

5 3.0 L 627 C

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Name______________________ GAS (law) STATIONS!!

Visit each station and follow the directions given below. Observations are the key so be sure to make notes before, during and after.

Station 1: Egg in a bottle demonstration!

Conclusions:

1. Which gas law that we have learned does this station illustrate? ___________________________________________________________________

What is that relationship: ________________________________________________

Station 2:

• Place a bit of water (5 ml) into a 125 ml flask. • Fit a balloon over the top of the flask and place in a hot water bath. • After 4 min., place the flask in an ice bath. • Clean up you station. Please take the balloon off the flask before you leave.

Conclusions:

2. Which gas law that we have learned does this station illustrate? ___________________________________________________________________

3. What is that relationship: ________________________________________________

Station 3:

• Using a 250 ml flask, place a balloon over the opening with the balloon inside of the flask. • Blow up the balloon in the flask until it completely fills the flask.

Conclusions:

1. Which gas law that we have learned does this station illustrate? ______________________________________________________________

2. What is that relationship: ________________________________________________

Station 4:

• Blow up a balloon, tie it off • Try to squeeze it to half its size without breaking it. If it breaks make note of

the fact and move on.

Conclusions:

1. Which gas law that we have learned does this station illustrate? ___________________________________________________________

2. What is that relationship: _______________________________________

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Skill 6: Use Combined Gas Law Equation

P = pressure (kPa or atm)

V = volume (L, mL, cm3)

T = temperature (K)

Combined Gas Law 1. A 280.0 mL sample of neon exerts a pressure of 660.0 atm at 26.0°C. At what temperature, °C,

would it exert a pressure of 940. atm in a volume of 440.0 mL? (396°C)

2. A certain gas has a volume of 500.0 mL at 77.0°C and 0.79 atm. Calculate the temperature, °C, if the volume decreased to 400.0 mL and the pressure is increased to 1.00 atm. (81.9°C)

𝑷𝟏𝑽𝟏𝑻𝟏

=𝑷𝟐𝑽𝟐𝑻𝟐

Combined gas law examples: A 45 mL sample of gas at standard pressure is heated from 20.°C to 50.°C. The pressure of the gas increases to 107.9 kPa. What is the new volume of the gas? If the Kelvin temperature of a gas sample is doubled while the pressure is halved, what will happen to the volume of the gas? (make up numbers and plug into equation)

P1V1 = P2V2 (10)(1) = (5) X X = 4

T1 T2 10 20 The volume of the gas will quadruple!

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3. A given sample of gas has a volume of 4.20 L at 60.0°C and 1.00 atm pressure. Calculate its pressure if the volume is changed to 5.00 L and the temperature to 27°C. (0.76atm)

4. A certain gas occupies a volume of 550.0 mL at STP. What would its volume be at 27.0°C and 1000ml.

5. Air bags are an important safety feature in modern automobiles. An air bag is inflated in milliseconds by the explosive decomposition of NaN3(s). The decomposition reaction produces N2(g), as well as Na(s), according to the unbalanced equation below.

__ NaN3(s) à___ Na(s) + ___ N2(g)

(a) Balance the above equation using the smallest whole-number coefficients.

(b) When the air bag inflates, the nitrogen gas is at a pressure of 1.30 atmospheres, a temperature of 301 K, and has a volume of 40.0 liters. Calculate the volume of the nitrogen gas at STP.

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Name_________________________________ Station Quiz Review - Boyle’s, Charles’, Combined Gas Laws

Solve all problems – you must show your work (including units). 1. A sample of gas occupies 400.0 mL at STP. Under what pressure would this sample occupy 200.0 mL if the temperature were increased to 819°C?

2. A gas sample contained in a cylinder equipped with a moveable piston occupied 300.0 mL at a pressure of 2.00 atm. What would be the final pressure if the volume were increased to 500.0 mL at constant temperature?

3. A weather balloon is filled to the volume of 150.0 L on a day when the temperature is 10.0°C. If no gases escaped, what would be the volume of the weather balloon after it rises to an altitude where the temperature is -8.00°C?

4. A sample of gas occupies a volume of 7.50 L at 0.988 atm and 28.0°C. At what temperature, in degrees Celsius, is the volume of the gas 4.00 L if the pressure is kept constant.

5. A sample of krypton gas occupies 75.0 mL at 0.400 atm. If the temperature remained constant, what volume would the krypton occupy at 0.0400 atm?

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Skill 7: Diffusion and Effusion:

Examples:

1. Does an atom of neon effuse faster or slower than C2H2?

2. Which will effuse faster, N2 or H2?

3. A carbon dioxide molecule travels at 45.0 m/s at a certain temperature. At the same temperature, will an oxygen molecule travel faster or slower?

4. Hydrogen sulfide, H2S, has a very strong rotten egg odor. Methyl salicylate, C8H8O3, has a wintergreen odor, and benzaldehyde, C7H6O, has a pleasant almond odor. If the vapors for these three substances were released at the same time from across a room, which odor would you smell first? Show your work and explain your answer.

Diffusion: Molecules moving from areas of ______ concentration to _____ concentration.

Example: Perfume molecules spreading across the room.

Define: Effusion - Gas _____________ through a tiny hole in a container.

o Both depend on the speed of the molecules o Bigger molecules move slower at the same temp. o Bigger molecules effuse and diffuse slower o Helium effuses and diffuses faster than air -escapes from balloon.

Page 17: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Skill 8: Dalton’s Law: Partial Pressure

Partial Pressure Problems:

1. A mixture of oxygen, nitrogen, and hydrogen gases exerts a total pressure of 74.0 kPa at 0ºC. The partial pressure of the oxygen is 20.0 kPa and the partial pressure of nitrogen is 40.0 kPa. What is the partial pressure of hydrogen in this mixture?

2. A mixture of gases in a closed container has a total pressure of 5 atm. Oxygen has partial pressure of 2atm. Argon exerts a pressure of 1.5 atm. What is the partial pressure of the 3rd gas, helium?

3. A cylinder is filled with 2.00 moles of nitrogen, 3.00 moles of argon, and 5.00 moles of helium. If the gas mixture is at STP, what is the partial pressure of the argon?

4. If 4.00 moles of oxygen gas, 3.00 moles of hydrogen gas, and 1.00 moles of nitrogen gas are combined in a closed container at standard pressure, what is the partial pressure exerted by the hydrogen gas?

Dalton’s Law: The total pressure in a container is the _______ of the partial pressures of all the gases in the container.

Ptotal = P1 + P2 + P3 + …

Example: The total pressure of three gas components in a mixture is 550 kpa. If the pressure of gas A is 200 kpa and the pressure of gas B is 75 kpa, what is the partial pressure of gas C?

Mole Questions: CREATE A RATIO

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Name__________________________ Dalton’s Law of Partial Pressures

1. What is the total pressure exerted by a mixture containing two gases if the partial pressure of one gas is 70. torr and the partial pressure of the other gas is 30. torr?

2. A 1-Liter flask contains two gases at a total pressure of 3.0 atmospheres. If the partial pressure of one of the gases is 0.5 atmospheres, then the partial pressure of the other gas must be what?

3. A mixture of oxygen, nitrogen, and hydrogen gases exerts a total pressure of 740. mmHg at 0°C. The partial pressure of the oxygen is 200. mmHg and the partial pressure of nitrogen is 400. mmHg. What is the partial pressure of the hydrogen gas in this mixture?

4. A sealed flask contains 1 mole of hydrogen and 3 moles of helium at 20°C. If the total pressure is400 atm, the partial pressure of the hydrogen is?

5. A 300.-milliliter container that is filled with 100. milliliters of oxygen and 200. milliliters of hydrogen has a total pressure of 750. millimeters of mercury. What is the partial pressure of the oxygen?

Page 19: Unit 9 Notes: Gas Laws Skills - StarpointLearns - Homestarpointlearns.weebly.com/uploads/5/9/0/7/59076643/k… ·  · 2016-02-06Kinetic Molecular Theory (KMT): Model that explains

Skill 9: Vapor Pressure

Vapor Pressure: Any liquid in a closed system produces a vapor that exerts pressure on the container it is in.

• As the temperature increases, the vapor pressure

____________________ (liquid to gas faster)

• As the temperature decreases, the vapor

pressure____________ (liquid to gas slower)

Substances that have ____________________ forces of

attraction have higher vapor pressure and Have low

boiling point

• Substances that have strong forces of attraction have lower vapor pressure and have _________

boiling points

Atmospheric Pressure: Normal Boiling Point Vapor Pressure

Intermolecular Force Review

o London Dispersion: • Also known as: ________________ • Distortions in molecule charge caused by the______________ of molecules. • WEAKEST INTERMOLECULAR FORCE

o Dipole-dipole: • Occurs between ________ molecules.

o Hydrogen Bonding: o Special, strong dipole-dipole IMF between a hydrogen and _________, ___________ or

__________.REMEMBER: Hydrogen bonding is FON!

Vapor Pressure and IMF:

The _____________ the intermolecular forces between the molecules, the ___________ it is for vaporization to occur, since more energy is required to break the bonds holding the molecules together!

Practice: Predict which compound in each pair will have the higher boiling point. (a) CS2 or CCl4 c) Cl2 or F2

(b) HI or KI (d) Na2O or H2O

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Skill 10: Using Table H

Practice:

Table H will allow you to determine boiling points of four liquids at different vapor pressures in kPa. Curves measure the temperature vs the vapor pressure.

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Answer:

1. Using your knowledge of chemistry and the information in Reference Table H, which statement concerning propanone and water at 50°C is true? (1) Propanone has a higher vapor pressure and stronger intermolecular forces than water. (2) Propanone has a higher vapor pressure and weaker intermolecular forces than water. (3) Propanone has a lower vapor pressure and stronger intermolecular forces than water. (4) Propanone has a lower vapor pressure and weaker intermolecular forces than water.

2. As the pressure on the surface of a liquid decreases, the temperature at which the liquid will boil (1) decreases (2) increases (3) remains the same

3. Which liquid has the highest vapor pressure at 75°C? (1) ethanoic acid (3) propanone (2) ethanol (4) water

4. Which liquid has the lowest vapor pressure at 65°C?

(1) ethanoic acid (3) propanone (2) ethanol (4) water

5. Which compound has the lowest vapor pressure at 50°C?

(1) ethanoic acid (3) propanone (2) ethanol (4) water

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Skill 11: Density Calculations and Molar Quantities

Finding Density at STP:

1. What is the density of 1 mole of H2O

2. What is the density of 1 mole of He?

3. What is the density of 2 moles of NaOH

Finding Molar Mass or Molar Volume at STP:

1. A sample of N2 gas has a density of 1.25g/l. Find the molar mass of this sample.

2. A sample of a gaseous compound has density of sulfur and oxygen has a density of 2.14g/l. what is the molar mass of this compound?

a. Determine the formula of this compound:

3. A sample gaseous of H2O has a density of .837g/l. Find the molar mass of this sample

4. A sample of a gaseous compound containing aluminum and chlorine has a density of 4.375g/l. Find the molar mass of this compound and the formula.

𝑫 =𝑴𝒐𝒍𝒂𝒓 𝑴𝒂𝒔𝒔𝑴𝒐𝒍𝒂𝒓 𝑽𝒐𝒍𝒖𝒎𝒆

MolarMass:TheGFMfromthePeriodicTable.

MolarVolume:22.4litersatSTPforANYgas.

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Skill 12: Convert between moles and liters

1. Determine the volume, in liters, occupied by 0.030 moles of a gas at STP.

0.030 mol ⎟⎟⎠

⎞⎜⎜⎝

moleL

14.22

= 0.67 L

2. How many moles of argon atoms are present in 11.2 L of argon gas at STP?

3. What is the volume of 0.05 mol of neon gas at STP?

4. What is the volume of 1.2 moles of water vapor at STP?

5. At STP, how many moles are in a gas sample with a volume of 16.8 L?

6. Given the reaction at STP: 2 KClO3(s) --> 2 KCl(s) + 3 O2(g)

How many liters of O2(g) are produced from the decomposition of 0.0250 mol of KClO3(s)?

7. Calculate the number of liters water produced by the complete reaction of 14.5 moles of oxygen.

2H2 + O2 → 2H2O

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Name____________________________ Gas Law Review

Technical Chemistry - Gas Laws Magic Squares. You must show your work in the square.

A. A sample of neon gas occupies a volume of 2.8 L at 1.8 atm. What would its volume be at 1.2 atm?

B. A balloon full of air has a volume of 2.75 L at a temperature of 18oC. What is the balloon's volume at 45 oC?

C. If 3.0 L of a gas at 20.0 oC is heated to 30.0 oC what is the new volume of the gas?

D. A sample of argon has a volume of 0.43 mL at 24 oC. At what temperature in degrees Celsius will it have a volume of 0.57 mL?

E. To what pressure would you have to compress 48.0 L of oxygen gas at 99.3 kPa in order to reduce its volume to 16.0 L?

F. If a barometer at your lab reads 2.5atm what is the atmospheric pressure in kPa?

G. What is the starting volume of a 24.7L gas sample that exerts a pressure of 0.999 atm. It’s original pressure being 1.011 atm.

H. What is the starting temperature of 150mL of gas when cooled to 33OC and a volume of 120mL

I. What is the volume occupied by 20.4 liters of CO2 at 1200 kpa when it is at STP?

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Name: _______________________________Review Packet KMT Date: _____________

1. When a given sample of a gas is held at constant temperature: a. The moles of molecules are inversely proportional to the temperature b. As the pressure increases there are additional gas molecules c. As the pressure increases the volume increases d. The volume and pressure are inversely proportional

2. Which of the following is the most likely explanation of why real gases do not exactly follow the gas laws?

a. Molecules of gases have attractive forces for one another b. Gas molecules do not take up space c. Gas molecules expand to fill their containers d. Molecules of gases collide with the walls of their containers

3. As the temperature of an enclosed gas is raised, which of the following is true? a. The attractive forces among molecules increases b. The volume and number of gas molecules increases c. A different value for the universal gas constant (R) must be used for each temperature d. The gas behaves more closely to ideal

4. Which of the following gases will diffuse most rapidly? a. C4H8 b. C2H6 c. H2O d. CH4

5. The graph to the right could be a graph of the relationship between: a. Pressure and volume of a gas b. Volume and temperature of a gas c. Number of moles and temperature of a gas

6. What will the new volume of a gas be if 40.0 ml of it at 27°C and 1140 mmHg is changed to standard conditions?

7. What pressure must a balloon be subjected to in order to change its volume to 5.6 L if it started out at 3.8 L and 102 kPa? The temperature has remained constant.

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8. Is the velocity of helium gas faster or slower than neon gas if they are diffusing at the same temperature?

9. What is the density of NH3 (g) at STP?

10. A gas, which initially occupied 2.25 L at 105 kPa and 27°C, has a mass of 2.5g at 650 kPa and 125°C. What is the density of this gas?

Definitions:

1. Boyle’s Law –

2. Charles’ Law –

3. Dalton’s Law of Partial Pressures –

Formulas:

1. What is the formula for the combined gas law?

4. What is the formula for Boyle’s law?

5. What is the formula for Charles’ law?

Short Answer:

6. What happens to the volume of a gas if the temperature is increased?

7. What happens to the volume of a gas if the temperature is decreased?

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8. What happens to the volume of a gas if the pressure is increased?

9. What are the conditions which make for an ideal gas?

Calculations:

15. If 2.4 L of gas is at a pressure of 387 kPa, what would the pressure be if the volume was expanded to 29.8 L?

17. Argon occupies a volume of 28.3 L at a pressure of 50 kPa. Find the volume of argon when the pressure is increased to 310 kPa.

18. A rigid container of oxygen gas has a pressure of 180 kPa at a temperature of 351 K. What is the pressure at 193 K?

19. A plastic bottle contains 32.5 L of gas at a pressure of 45.7 kPa and is compressed to a volume of 4.1 L. What would be the new pressure?

22. If a gas at 35.0°C is pressurized from 160 kPa to 250 kPa, what would be the final temperature?

24. A balloon has a volume of 43.6 L at 310 K. What is the temperature of the balloon if the volume is decreased to 27.8 L?

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