42 Learning Materials and Exercises
Absolute Zero Explained
Textbook Material
Read:
Chapter 13
Temperature, Kinetic Theory, and the Gas Laws
13.2 Thermal Expansion of Solids and Liquids
13.4 Kinetic Theory: Atomic and Molecular Explanation of Pressure and Temperature
13.6 Humidity, Evaporation, and Boiling
Main Ideas
Temperature
- Temperature is the quantity measured by a thermometer.
- Temperature is related to the average kinetic energy of atoms and molecules in a system.
- Absolute zero is the temperature at which there is no molecular motion.
- There are three main temperature scales: Celsius, Fahrenheit, and Kelvin.
The zeroth law of thermodynamics
If two systems, A and B, are in thermal equilibrium with each other, and B is in thermal equilibrium with a third system, C, then A is also in thermal equilibrium with C.
Moles and Avogadro’s number
- A mole (abbreviated mol) is defined to be the amount of a substance that contains as many atoms or molecules as there are atoms in exactly 12 grams (0.012 kg) of carbon-12.
- Avogadro’s number is the number of atoms or molecules in 1 mole.
- [latex]N_A[/latex]=6.02 x 1023 mol-1.
The Ideal Gas Law
The ideal gas law relates the pressure and volume of a gas to the number of gas molecules and the temperature of the gas.
[latex]PV=NkT[/latex],
[latex]P[/latex] is gas pressure, [latex]V[/latex] is gas volume, [latex]N[/latex] is number of molecules, [latex]k[/latex] is the Boltzmann constant = 1.38 x 10-23 J/K, [latex]T[/latex] is temperature.
Phase changes
- Most substances have three distinct phases: gas, liquid, and solid.
- Phase changes among the various phases of matter depend on temperature and pressure.
Solving Thermodynamics Problems: A strategy
- Summarize given information in your own words; leave out unneeded information.
- Draw a sketch of the situation.
- Define system boundaries (note if it is an open or closed system).
- Identify knowns and unknowns.
- Choose the laws of thermodynamics suitable for the situation.
- Determine what properties are involved and how to find values for them.
- Describe the process in terms of the change in system properties.
- Substitute numbers into the equation and solve for the unknown complete with units.
- Does answer make sense?
Textbook Exercises
Solve the following problems.
Chapter 13
- Conceptual Questions: 1 – 3, 6, 7, 10 – 12.
- Problems & Exercises: 1 – 5, 22, 25, 28, 29, 30, 32.
Solving Problems in Physics
Note: Image by Chudaeva, E. (2022).
Formulas
Modify this list as you wish to support your learning.
Elena’s explanation of how to approach and solve problems on temperature and gas laws
Check this handout with problems and steps involved in solving these problems and thinking processes that Elena used to solve these problems.
Modify this handout as you wish to support your learning.
Additional Resource
This OpenStax Chemistry textbook (chapters 9 and 10) may support your learning. Check it out.
