Define a system

The system is what we are interested in, ie the reaction vessel

Define the surroundings

The surroundings describes all space that is not the system in question

Draw and describe an open system

Matter and energy can be exchanged with the surroundings. Eg an open beaker left to evaporate

Draw and describe a closed system

Only energy can be exchanged with the surroundings, eg a reaction in a sealed tube

Draw and describe an isolated system

Neither energy nor matter can be exchanged with the surroundings eg hot liquid in a thermos

Describe Temperature, T

Measured in Kelvin. 0°C = 273.15K

Describe Volume, V

The SI unit for volume is m^{3}

Describe pressure, P

Force, F (N) per area, A (m^{2})

The SI unit is Pa but there are many other units of pressure

Define one bar

1 bar = 10^{5} Pa

Define one atm

1 atm = 101.325 kPa

Define the standard pressure in thermodynamics

1 bar (10^{5} Pa) is defined as the standard pressure, p^{0}

Give the equation linking amount of substance to mass

Give the equation linking mole fraction and number of moles

Describe Avogadro's principle

For a system in which temperature and volume are fixed, pressure increases as gas is fed into the system.

Describe Boyle's law

For a system where n and T are fixed, volume and pressure are inversely proportional. ie pV = constant

Describe Guy-Lussac's law

For a system in which n and V are fixed, pressure increases as temperature increases

Describe how to derive the ideal gas law.

By combining Avogadro's principle (p ∝ n), Boyle's law (p ∝ 1/v) and Guy-Lussacs law (p∝T) we can get the ideal gas law:

Give the value for R, the gas constant

Describe an ideal gas

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- The volume of the gas molecules = 0 (negligible)
- There are no interactions between molecules
- The gas does not become a liquid or solid upon cooling

Define an isothermic process

One which takes place at constant temperature

Define an isochoric process

One which takes place at constant volume

Define an isobaric process

One which takes place at constant pressure

Describe Dalton's law of partial pressures

If we have a mixture of gases A and B, their partial pressures can be worked out.

total p = p_{A} + p_{B}

Mole fractions can be worked out using partial pressures:

n_{A}/(n_{A} + n_{B}) = p_{A}/p