Ideal Gas Laws

Question 1

What is an ideal gas?

Answer 1

A gas that obey’s Boyle’s Law at all temperatures.

Question 2

Boyle’s Law, Charles’ Law and the pressure law can be combined to give:

Answer 2

pV/T = constant for a fixed mass of ideal gas.

Question 3

What is the molar gas constant?

Answer 3

8.31 Jmol^-1K^-1

Question 4

Ideal gas equation

Answer 4

pV = nRT

Question 5

In 1811 Amadeo Avogadro predicted that:

Answer 5

Equal volumes of gases at the same temperature andpressure contain equal numbers of molecules.

Question 6

What is the Avogadro constant?

Answer 6

The number of atoms in exactly 12g of the carbon-12. NA is used to define the mole. Its value is 6.02x10²³ mol^-1.

Question 7

What is one mole of a substance?

Answer 7

One mole of a substance consisting of identical particles is the quantity of substance that contains N_A particles of the substance.

Question 8

What is molarity?

Answer 8

The number of moles in a certain quantity of a substance. The unit is in mols.

Question 9

What is molar mass?

Answer 9

Molar mass is the mass of 1 mole of the substance. Unit is kgmol^-1

Question 10

The number of moles ,N, in mass M_S =

Answer 10

M_S/M

Question 11

The number of molecules in M_S

Answer 11

N_AM_S/M

Question 12

Gas molecules:

Answer 12

• Undergo collisions with other particles
• Move at different speeds
• Move randomly (i.e. their movement cannot be predicted).

Question 13

Density of an ideal gas =

Answer 13

M_S/V = pM/RT

Question 14

What is the Boltzmann constant?

Answer 14

k

The molar mass constant over the avogadro constant

1.38×10⁻²³JK^-1

Question 15

Second ideal gas equation

Answer 15

pV = NkT