1.7 Kinetic Theory

what is the definition of a gas?

a state of a substance which expands to fill any volume that it is placed in

what are 4 examples of thermodynamic, measurable quantities?

pressure, temperature, volume, number of moles

what is pressure?

the force experienced on one unit area of surface in contact with the gas

what is temperature?

a measure of the average kinetic energy of the particles in the gas

what is temperature measured in?

kelvin

what is volume?

a measure of the total space occupied by the gas

what are moles?

a measure of the number of particles in the gas, 1 mol = 6.02 ×10²³ particles

what is boyle’s law?

when temperature is constant, pressure is inversely proportional to volume

what is charles’s law?

when pressure is constant, volume is proportional to temperature

what is the pressure law?

when volume is constant, pressure is proportional to temperature

what is the value of the boltzmann constant?

1.38 × 10^-23

what does N stand for?

the total number of particles

what does N_A stand for?

Avogadro’s Number

what does n stand for?

the number of moles

what is the relative molecular mass?

the mass of a molecule, relative to 1/12th that of Carbon-12

what is molar mass?

the mass per mole

how can we calculate the molar mass?

relative molecular mass / 1000

what does the ideal gas equation describe?

a gas which has a number of properties that real physical gasses do not have

what are the properties of an ideal gas?

• no intermolecular forces

• the size of particles is negligible compared to the volume of gas

• the collisions between particles are perfectly elastic

• the motion of particles is purely random

what is no intermolecular forces equivalent to saying?

the particles only carry kinetic energy

when can we approximate a real gas to behave like an ideal gas?

when the temperature is large and the pressure is small

why cant a gas be ideal if its pressure is too large?

the potential energy associated with the distance between particles will become more significant compared to their kinetic energy

what is pressure caused by?

collisions between the particles and container walls

what is force?

the rate of change of momentum

what is the average kinetic energy of a gas particle proportional to?

the temperature of the gas