IDEAL GAS LAW

IDEAL GAS LAW

AVOGADRO'S LAW

- 1811, Amadeo Avogadro

- a statement that under the same conditions of temperature and pressure, equal volumes of different gases contain an equal number of molecules

AVOGADRO'S LAW

- approximately valid for real gases at sufficiently low pressures and high temperatures.

Multiple Choice

What is will happen to the volume if the number of particles inside the container was doubled?

• halved

• doubled

• quartered

• tripled

AVOGADRO'S LAW

V = kn

V1/n1 = V2/n2

V - volume

n - no. of gas in mol

AVOGADRO'S NUMBER/ CONSTANT

specific number of molecules in one gram-mole of a substance, defined as the molecular weight in grams, is 6.02214076 × 10²³

AVOGADRO'S NUMBER/ CONSTANT

from this law is that if samples of any gas are compared that have the same volume, temperature and pressure, then they will all have the same number of molecules in them.

Multiple Choice

Which of the following graphs can be used to represent Avogadro's Law

Multiple Choice

A 6.0 L sample at 25°C and 2.00 atm of pressure contains 0.5 mole of a gas. If an additional 0.25 mole of gas at the same pressure and temperature are added, what is the final total volume of the gas?

• 6.0 L

• 7.0 L

• 8.0 L

• 9.0 L

IDEAL GAS LAW

Ideal gases are essentially point masses moving in constant, random, straight-line motion

IDEAL GAS LAW

PV = nRT

P - pressure

V - Volume

n - no. of mol

R - gas constant (8.31 J/K mol or 0.082 L atm/K mol)

T - temperature

Multiple Choice

5.0 g of neon is at 256 mm Hg and at a temperature of 35º C. What is the volume?

• 19 L

• 15 L

• 20 L

• 10 L

Kinetic Molecular Theory of Gases

molecules of a gas are in a state of perpetual motion in which the velocity of each molecule is completely random and independent of that of the other molecules.

Kinetic Molecular Theory of Gases

A gas is composed of molecules that are separated by average distances that are much greater than the sizes of the molecules themselves. The volume occupied by the molecules of the gas is negligible compared to the volume of the gas itself.

Kinetic Molecular Theory of Gases

The molecules of an ideal gas exert no attractive forces on each other, or on the walls of the container.

Kinetic Molecular Theory of Gases

The molecules are in constant random motion, and as material bodies, they obey Newton's laws of motion.

Kinetic Molecular Theory of Gases

Collisions are perfectly elastic; when two molecules collide, they change their directions and kinetic energies, but the total kinetic energy is conserved. 

Kinetic Molecular Theory of Gases

The average kinetic energy of the gas molecules is directly proportional to the absolute temperature.