Chemistry Name:_________________________________ Hood River Valley High Period:_________

Unit 7 – States of Matter and the Behavior of Gases Unit Goals- As you work through this unit, you should be able to:

1. Describe, at the molecular level, the difference between a gas, liquid, and solid phase. 2. Explain gas behavior using the kinetic molecular theory. 3. Relate attractive forces to boiling points and vapor pressure. 4. Interpret a phase diagram and describe the significance of the triple point. 5. Describe the four variables that define a gaseous system quantitatively 6. Use STP to determine the amount of gas used or produced in a chemical reaction. 7. Use ideal gas behavior and solve the following gas laws:

Charles's Law Combined Gas Law Boyle's Law Ideal Gas Law Gay-Lussac’s Law

8. Understand how gas mixtures and movements are described by the following gas laws: Dalton’s Law of Partial Pressures & Graham’s Law

Assignments: Activities, Labs & Test

Description Goals 5 4 0 Gas Variable Candle Lab

A1 Kinetic

Molecular Theory WS

1 – 2

Charles Law Lab

Boyles Lab

A2 Relationship b/w gases & liquids WS

2 – 4

Ideal & Part. Press. Lab

Egg Suck and Shoot 4 Variable Lab

A3 Boyle’s, Charles,

Gay-Lussac’s Law WS

5-7

Unit 7 Test

Late Lab Stamp (this stamp means you are not qualified to do lab and

test corrections) A4 Combined and Ideal Gas Law

WS 5-7

A5 Dalton’s and

Graham’s Law WS

8

A6 Unit 7 Review 1-8

Readings: Ch. 13: (pp 384-395, 401-411) Sections 13.1, 13.2, 13.4, Ch. 14: (pp 412-443) Sections 14.1 – 14.4

Key Terms: kinetic molecular theory, pressure, barometer, absolute temperature scale, vapor pressure, forces of attraction, normal boiling point, sublimation, phase diagram, triple point, normal freezing point,Avogadro's Hypothesis, standard temperature and pressure, Charles's Law, Boyle's Law, Graham's Law, Combined Gas Law, ideal gas, Ideal Gas Law, Dalton's Law of Partial Pressure

Demo’s: See Demo Packet

Chapter 13 Goal 1: States of Matter

• __________________________________ • Forces between particles of a substance. Intermolecular Forces. Hold particles together.

• __________________________________ • Energy of Motion. Related to mass and speed of particles • KE = ½ mv2

• __________________________________ • Measure of Average Kinetic Energy of a sample. As temperature increases, particles

move faster in a sample

• __________________________________ • Collisions between atoms and molecules are ELASTIC. This means Kinetic Energy is

conserved. TEMPERATURE is NOT lost due to Collisions. Collisions result in PRESSURE

SOLID LIQUID GAS

Attractive Forces between Particles

Volume & Compressibility

Molecular Motion

13.1 The Nature of Gases Goal 2: Kinetic Molecular Theory Kinetic Theory and a Model for Gases: Page 420

• Describes the MOTION of gas particles • 3 Statements of the Theory

1. The particles in a gas are considered to be ________, _____________ with an insignificant volume: ____ attractive or ________________ forces exist between them.

2. The particles of a gas travel in ___________, constant, and _______________ motion. They travel in _______________line paths that are _______________of eachother.

3. All collisions between particles are perfectly _______________(no kinetic energy is lost). The total ______________energy of the gas particles remains ________________.

Kinetic Molecular Theory helps explain: PRESSURE, VOLUME, and TEMPERATURE

• Pressure • Number of ______________that take place.

More collisions = More ______________. • Volume

• Space that ______________take up. Particles will completely fill a ______________with their ______________motion.

• Kinetic Energy and Temperature • Average ______________Energy of ______________ • Related to _____________of particles. Greater Speed = Greater _____________.

Temperature Theory: Kelvin Scale Page 424

• What is absolute 0? • How was 0K found? • Why use Kelvin?

13.2 The Nature of Liquids Goal 3: Attractive Force Affects (Vapor Pressure: Page 427)

• The pressure caused by ______________gas particles pushing ____________upon a liquid • Stronger attractive forces result in ______________Vapor pressures • At ______________temperatures vapor pressure increases • More molecules evaporate at ______________temperatures • Water: ___________vapor pressure

Boiling Point: Page 428 • Temperature at which ___________pressure equals ___________pressure.

• The liquid goes beyond just ___________at Boiling Point. • Gas bubbles begin to form ___________the liquid. • ___________attractive forces result in ___________BP’s

Volatility

• Likelihood of a liquid ___________. • ________Volatility: Liquid has ________vapor pressure • Liquid is ________likely to evaporate – produce _________vapor • High Volatility: Liquids with __________attractive forces • Water: _________volatility

Surface Tension

• ___________force (pull) between the ___________of a liquid on the ___________. • High Surface Tension: Holds a liquid into ________. • Liquids with very ___________attractive forces have __________surface

tension • Water: ________surface tension

13.4 Changes of State Goal 4: Phase Diagrams: Page 438

• Triple Point

Chapter 14

14.1 Goal 5: Gas Variables • 4 variables define a gas system

• Pressure: (P) – Units:

» Pascal (Pa) » Atmospheres (atm) » Millimeters of Mercury (mm Hg) » _____________________________

• Volume: (V) – Units:

» Liters (L), milliliters (mL), (cm3)

• Temperature: (T) – Units:

» Celsius (°C) » Kevin (K) » Kelvin is the Official Unit » _____________________________________

• Number of Particles: (n) – Unit: Moles (mol)

Goal 6: Gases and Moles review • At STP: 1mol = 22.4L

• STP: Standard Temperature and Pressure » »

• Review • 1 mol = • 1 mol = • 1 mol =

Stoichiometry Examples Li3N(g) + 3H2O(l) NH3(g) + 3LiOH(aq)

• What mass of water is needed to react with 29.3 L of Li3N?

• When 13.3 L of NH3 are produced how many formula units of LiOH are produced?

• Given 7.8 moles of LiOH produced, what volume of Li3N was used?

Math Review (k = constant)

• Direct Relationship • Generic Equation

Y = kX (k is a constant) k = Y/X

• Graph

• Inverse Relationship • Generic Equation

Y = k/X (k is a constant) k = XY

• Graph

14.2 The Gas Laws Goal 7: Gas Laws

• Boyles:

• Charles:

• Gay-Lussac’s:

• Combined:

Boyles Law: At constant TEMPERATURE: • Pressure and Volume are INVERSE • PV = constant • P1V1 = P2V2

Graph of P vs. V:

• As Pressure increases Volume ___________

Practice Boyles Law #1: Nitrous oxide (N2O) is used as an anesthetic. The pressure on 2.50 L of N2O changes from 105 kPa to 40.5 kPa. If the temperature does not change, what will the new volume be? Practice Boyles Law #2: A gas with a volume of 4.00 L at a pressure of 205 kPa is allowed to expand to a volume of 12.0 L. What is the pressure in the container if the temperature remains constant?

Charles Law: At constant PRESSURE: • Temperature and Volume are DIRECT • V/T = constant

Graph of V vs. T:

• As Temperature increases Volume __________

Practice Charles Law #1: A balloon inflated in a room at 24⁰C has a volume of 4.00 L. The balloon is then heated to a temperature of 58⁰C. What is the new volume if the pressure remains the same? (pg 459) Practice Charles Law #2: If a sample of gas in a balloon occupies 6.8 L at 325 C, what is the temperature if the volume later is found to be 4.2L if the pressure does not change?

Gay-Lussac’s Law: Page 460 • At constant VOLUME: • Temperature and Pressure are DIRECT • P/T = constant

Graph of P vs. T:

• As Temperature increases Pressure ________

Practice Gay-Lussac’s #1: Aerosol cans carry labels warning not to incinerate (burn) the cans or store them above a certain temperature. This problem will show why it is dangerous to dispose of aerosol cans in a fire. The gas in a used aerosol can is at a pressure of 103 kPa at 25⁰C. If the can is thrown onto a fire, what will the pressure be when the temperature reaches 928⁰C? Practice Gay-Lussac’s #2: The pressure iin a car tire is 198 kPa at 27 ⁰C. After a long drive, the pressure is 225 kPa. What is the temperature of the air in the tire? Assume that the volume is constant.

Combined Gas Laws: Page 462

• All 3 laws put together

Practice Combined #1: The volume of a gas-filled balloon is 30.0 L at 313 K and 153 kPa pressure. What would the volume be at STP? (pg 462) Practice Combined #2: A gas at 155 kPa and 25 C occupies a container with an initial volume of 0.010 L. By changing the temperature, the pressure of a gas increases to 605 kPa and the volume increases to 2.4 L. What is the new temperature? Practice Combined #3: A 5.00 L air sample at a temperature of – 50 C has a pressure of 107 kPa. What is the new pressure if the temperature is raised to 102 C and the volume expands to 7.00 L?

14.3 Ideal Gases Ideal Gas Law: Page 464:

• Ideal Gas Law includes number of _____________into the calculation. • How does it work? n = ________

If kPa, R = If atm, R = If mmHg, R =

Ideal Gas Law • P: • V: • T: • n: • R:

PV=nRT Example 1: You fill a rigid steel cylinder that has a volume of 20.0 L with nitrogen gas to a final pressure of 20,000.0 kPa at 28 C. How many moles of nitrogen gas does the cylinder contain?

PV=nRT Example 2: Deep underground cavern contains 2.24 x 10^6 L of methane gas, CH4, at a pressure of 1.5 x 10^3 kPa and a temperature of 42 C. How many grams of methane does this natural-gas deposit contain? PV=nRT Example 3: What volume will 12 grams of oxygen gas occupy at 25 C and a pressure of 52.7 kPa? PV=nRT Example 4: When the temperature of a rigid hollow sphere containing 68.5 moles of helium gas is held at 621 L, the pressure of the gas is 1.89 x 103 kPa. What temperature is this container of helium? PV=nRT Example 5: What pressure will be exerted by 0.45 mol of a gas at 25 C if it is contained in a 0.65 L vessel?

14.4 Gases: Mixtures and Movements Dalton’s Law: Page 469, Goal 8:

• The total pressure of a gas _____________is the “_______” of the pressures of each

_____________ gas in the mixture • Pt =

• Each gas pressure depends on its %_____________

Mole Ratio’s and % abundance

Dalton Law Examples #1: A container has a mixture of atmosphere and water vapor. At 50°C the partial pressure of water vapor is 12.34 kPa. What is the pressure of the atmosphere gasses if the total pressure is 101.3 kPa? Dalton Law Examples #2: A container contains 10 g of oxygen gas, 80 g of nitrogen gas and 1 g of carbon dioxide. The total pressure of the container is 101.3 kPa, find:

– Mole fraction of each gas – The partial pressure of each gas

Graham’s Law: Page 472

• The velocity of particles is related to their temperature (ave. Kinetic Energy) and their mass. • KE = ½ mv2

• Therefore v =

• v is inversely proportional to the mass of the particle at any given temperature. • For 2 gases (A and B)

Graham Law Applications

• At the SAME _______________

• Molecules with _____________masses have _____________velocities

• Molecules with _____________masses have _____________velocities • DIFFUSION:

• The tendency of molecules to move toward areas of __________concentration.

• Molecules with greater _____________have _____________rates of diffusion • 2 effects on Diffusion rates:

1. 2.

Graham’s law Example 1: Compare the rate of diffusion of nitrogen gas to helium gas:

Graham’s law Example 2: Compare the rate of diffusion of argon to neon gas:

Graham’s law Example 3: What is the rate of effusion for a gas that has a molar mass twice that of a gas that effuses at a rate of 3.62 mol/min?

Graham’s law Example 4: An unknown gas effuses 1.66 times more rapidly than CO2. What is the molar mass of the unknown gas.