S1.5 Ideal gases

Ideal gas laws (5)

1. Particles r in constant random motion

2. Volume of gas is negligible to volume of container(it takes no space)

3. No intermolecular forces exist between gas particles

4. All collisions r perfectly elastic(no kinetic energy lost)

5. Temperature of gas (K), is directly proportional to avg kinetic energy of particles

What makes a real gas deviate from ideal gas behaviour? (3)

1. They have a finite.measurable volume

2. They have intermolecular forces between particles

3. They deviate most at low temperatures and high pressures

Relationship between pressure and volume of gas(Boyle’s law)

p→1/V

pV=k

p1V1=p2V2

Relationship between pressure and volume of gas(Boyle’s law)

p→1/V

pV=k

p1V1=p2V2

True or false: gases with weak intermolecular forces will show more deviation from ideal gas behaviour

False

Ideal gases have no intermolecular forces:

weak IF→less deviation

Strong IF→more deviation

What conditions allow real gases to be similar to ideal gases?

High temperatures

Low pressure

Avogadro’s law about gases volume

Gases occupying same volume under same t and p contain same amt of particles

What is the molar volume of 1 mol of an ideal gas at stp?

22.7 dm³/mol

How do u calculate the volume of a gas at stp?

V (dm³)= n x 22.7

Relationship between gas and temperature(Charles’ law)

V—>T(K)

V/T=k

More frequent collisions→gas must expand to keep p constants→V increases

Relationship between pressure and temperature

P→T(K)

P/T=k

How ideal gas eqn is constructed

What is the combined gas law and units involved?

T(K)

p(Pa→0.001 kPa)

V(m³→1000dm³)

p1V1/T1=p2V2/T2

What is the ideal gas equation and the units involved

pV=nRT

T(K)

p(kPa/Pa)

R=8.31 J/K mol

n(mol)

V(dm³/m³)

Differences between ideal and real gases

Graphs of Boyle’s law

Why might the molar mass value of a real gas be different when finding it using pV=nRT?

It’s not an ideal gas so it does not perfectly follow the ideal gas law