2. Click a hyperlink or folder tab to view the corresponding slides.
Gases
Section 13.1 The Gas Laws
Section The Ideal Gas Law
Section Gas Stoichiometry
Click a hyperlink or folder tab to view the corresponding slides.
Exit
Chapter Menu

3. Section The Gas Laws
State the relationships among pressure, temperature, and volume of a constant amount of gas.
Apply the gas laws to problems involving the pressure, temperature, and volume of a constant amount of gas.
scientific law: describes a relationship in nature that is supported by many experiments
Section 13-1

4. Section 13.1 The Gas Laws (cont.)
Boyle’s law
absolute zero
Charles’s law
Gay-Lussac’s law
combined gas law
For a fixed amount of gas, a change in one variable—pressure, temperature, or volume—affects the other two.
Section 13-1

5. P1V1 = P2V2 where P = pressure and V = volume
Boyle's Law
Boyle’s law states that the volume of a fixed amount of gas held at a constant temperature varies inversely with the pressure.
P1V1 = P2V2 where P = pressure and V = volume
Section 13-1

6. Kinetic-molecular theory explains this property.
Charles's Law
As temperature increases, so does the volume of gas when the amount of gas and pressure do not change.
Kinetic-molecular theory explains this property.
Section 13-1

7. Charles's Law (cont.)
Section 13-1

8. Absolute zero is zero on the Kelvin scale.
Charles's Law (cont.)
Absolute zero is zero on the Kelvin scale.
Charles’s law states that the volume of a given amount of gas is directly proportional to its kelvin temperature at constant pressure.
Section 13-1

9. Gay-Lussac's Law
Gay-Lussac’s law states that the pressure of a fixed amount of gas varies directly with the kelvin temperature when the volume remains constant.
Section 13-1

10. Gay-Lussac's Law (cont.)
Section 13-1

11. The Combined Gas Law
The combined gas law states the relationship among pressure, temperature, and volume of a fixed amount of gas.
Section 13-1

12. The Combined Gas Law (cont.)
Section 13-1

13. A B C D Section 13.1 Assessment
Boyle’s Law explains which relationship of properties in gases?
A. pressure and volume
B. amount and pressure
C. temperature and volume
D. volume and temperature A B C D
Section 13-1

14. A B C D Section 13.1 Assessment
Atoms are in their lowest energy state at what temperature?
A. 0° Celsius
B. 0° Fahrenheit
C. –100° Celsius
D. 0 kelvin A B C D
Section 13-1

15. Section 13.2 The Ideal Gas Law
Relate number of particles and volume using Avogadro’s principle.
Relate the amount of gas present to its pressure, temperature, and volume using the ideal gas law.
Compare the properties of real and ideal gases.
mole: an SI base unit used to measure the amount of a substance; the amount of a pure substance that contains 6.02 × 1023 representative particles
Section 13-2

16. Section 13.2 The Ideal Gas Law (cont.)
Avogadro’s principle
molar volume
ideal gas constant (R)
ideal gas law
The ideal gas law relates the number of particles to pressure, temperature, and volume.
Section 13-2

17. Avogadro's Principle
Avogadro’s principle states that equal volumes of gases at the same temperature and pressure contain equal numbers of particles.
Section 13-2

18. Avogadro's Principle (cont.)
The molar volume of a gas is the volume 1 mol occupies at 0.00°C and 1.00 atm of pressure.
0.00°C and 1.00 atm are called standard temperature and pressure (STP).
At STP, 1 mol of gas occupies 22.4 L.
Section 13-2

19. Combined gas law to ideal gas law
The Ideal Gas Law
Ideal gas particles occupy a negligible volume and are far enough apart to exert minimal attractive or repulsive forces on each other.
Combined gas law to ideal gas law
Section 13-2

20. The Ideal Gas Law (cont.)
The ideal gas constant is represented by R and is L•atm/mol•K when pressure is in atmospheres.
The ideal gas law describes the physical behavior of an ideal gas in terms of pressure, volume, temperature, and amount.
Section 13-2

21. The Ideal Gas Law (cont.)
Section 13-2

22. The Ideal Gas Law—Molar Mass and Density
Molar mass and the ideal gas law
Section 13-2

23. The Ideal Gas Law—Molar Mass and Density (cont.)
Density and the ideal gas law
Section 13-2

24. Real Versus Ideal Gases
Ideal gases follow the assumptions of the kinetic-molecular theory.
Ideal gases experience:
There are no intermolecular attractive or repulsive forces between particles or with their containers.
The particles are in constant random motion.
Collisions are perfectly elastic.
No gas is truly ideal, but most behave as ideal gases at a wide range of temperatures and pressures.
Section 13-2

25. Real Versus Ideal Gases (cont.)
Real gases deviate most from ideal gases at high pressures and low temperatures.
Polar molecules have larger attractive forces between particles.
Polar gases do not behave as ideal gases.
Large nonpolar gas particles occupy more space and deviate more from ideal gases.
Section 13-2

26. A B C D Section 13.2 Assessment
Which of the following is NOT one of the related physical properties described in the ideal gas law?
A. pressure
B. volume
C. density
D. temperature A B C D
Section 13-2

27. A B C D Section 13.2 Assessment
3.00 mol of O2 at STP occupies how much volume?
A L
B L
C L
D L A B C D
Section 13-2

28. Section 13.3 Gas Stoichiometry
Determine volume ratios for gaseous reactants and products by using coefficients from chemical equations.
Apply gas laws to calculate amounts of gaseous reactants and products in a chemical reaction.
coefficient: the number written in front of a reactant or product in a chemical equation, which tells the smallest number of particles of the substance involved in the reaction
When gases react, the coefficients in the balanced chemical equation represent both molar amounts and relative volumes.
Section 13-3

29. Stoichiometry of Reactions Involving Gases
The gas laws can be applied to calculate the stoichiometry of reactions in which gases are reactants or products.
2H2(g) + O2(g) → 2H2O(g)
2 mol H2 reacts with 1 mol O2 to produce 2 mol water vapor.
Section 13-3

30. Stoichiometry and Volume-Volume Problems
Coefficients in a balanced equation represent volume ratios for gases.
Section 13-3

31. Stoichiometry and Volume-Mass Problems
Mass must be found by converting to moles or volumes.
Plastics are some of the products created with polymers.
One component of polymers is ethene gas, or ethylene.
Section 13-3

32. A B C D Section 13.3 Assessment
How many mol of hydrogen gas are required to react with 1.50 mol oxygen gas in the following reaction?
2H2(g) + O2(g) → 2H2O(g)
A. 1.00
B. 2.00
C. 3.00
D. 4.00 A B C D
Section 13-3

33. A B C D Section 13.3 Assessment
How many liters of hydrogen gas are required to react with 3.25 liters of oxygen gas in the following reaction?
2H2(g) + O2(g) → 2H2O(g)
A. 2.00
B. 3.25
C. 4.00
D. 6.50 A B C D
Section 13-3