Thermodynamics MOC

Ideal gas

An ideal gas is an idealised gas for which the following assumptions hold:

1. Newton’s laws apply to the particles
2. The particles are identical and have effectively zero volume.
3. The particles are constantly engaged in random motion with a distribution of speeds independent of direction (Brownian motion).
4. There is no attraction or repulsion between gas particles or their surroundings. Therefore, there is no , only . Collisions between particles and the container walls are the only forces on the particles.
5. All collisions are elastic, i.e. no is lost.

One set of thermodynamic equations of state for an ideal gas are

1. Ideal gas law ()
2. Energy of an ideal gas ()

Further properties

• Specific heat of an ideal gas
• Entropy of an ideal gas

Types of ideal gas

Ideal gases come in three types inquire

1. Monoatomic — all its energy is translational since there are no axes of rotation, so we can calculate the Total energy in an ideal monoatomic gas. In general, only Noble gases take this form, e.g. , .
2. Diatomic — have rotational kinetic energy in one axis. Pure gases tend to take this form, e.g. , , .
3. Polyatomic — have multiple axes of rotation, e.g. .

---

tidy | sembr