__Temperature and Kinetic Theory__

## AP Objectives

*These are all the objectives stated in the AP course description that relate to thermal expansion, ideal gases, and kinetic theory:*

A. Thermal expansion (~2% of exam)

a) Analyze what happens to the size and shape of an object when it is heated.

B. Kinetic theory and thermodynamics (~7% of exam)

1. Kinetic model

a) State the assumptions of the model.

b) State the connection between temperature and mean translational kinetic

energy, and apply it to determine the mean speed of gas molecules as a function

of their mass and the temperature of the gas.

c) State the relationship among Avogadro’s number, Boltzmann’s constant, and

the gas constant R, and express the energy of a mole of a monatomic ideal gas

as a function of its temperature.

d) Explain qualitatively how the model explains the pressure of a gas in terms of

collisions with the container walls, and explain how the model predicts that, for

fixed volume, pressure must be proportional to temperature.

2. Ideal gases

a) Relate the pressure and volume of a gas during an isothermal expansion or

compression.

b) Relate the pressure and temperature of a gas during constant-volume heating or

cooling, or the volume and temperature during constant-pressure heating or

cooling.

c) Calculate the work performed on or by a gas during an expansion or

compression at constant pressure.

d) Understand the process of adiabatic expansion or compression of a gas.

e) Identify or sketch on a PV diagram the curves that represent each of the above

processes.

## Summary

__Constants__

## Moles

1 mol = 6.022*10^23 (atoms/molecules)

1 mol of Carbon-12 is defined to have a mass of 12g

Therefore, the mass of 1 mol of a certain atom/molecule has a mass equal to its atomic mass in grams.

1 mol of Carbon-12 is defined to have a mass of 12g

Therefore, the mass of 1 mol of a certain atom/molecule has a mass equal to its atomic mass in grams.

__Formulas__

## 1. Thermal Expansion

## 2. Gas Laws

**STP**- Standard Temperature and Pressure is defined to be at

**1 atm**(101325 Pa) and

**273.15K**

The ideal gas law can also be written as (when only changing P, V, and T for the same gas):

## Visualization of P vs V, P vs T, and V vs T graphs (and all 3 at the same time)

## 3. Kinetic Theory

**Postulates of Kinetic Theory**

KT assumes the following:

- There are
**many molecules**moving in random directions at various speeds. - The molecules are
**far apart**from each other. - The molecules
**only interact when they collide**(no EM or gravitational forces). - Collisions (with other molecules and the walls) are
**perfectly elastic**.

## KT Derivation

## Practice

Practice Questions | |

File Size: | 55 kb |

File Type: | doc |

Answer Sheet | |

File Size: | 83 kb |

File Type: | doc |

## AP Questions for the detail oriented

## More

## Thermal Expansion (includes 2D expansion)

## Thermal Expansion Lesson

## Gas Laws Refresher

## Gas Molecules Simulation

## Gas Law - P vs V

## Boyle's Law Demo

Steven Wang