Gases quiz

kinetic molecular theory says…

The collisions of the gas molecules with each other and with the walls of their container explain the relationship between the macroscopic properties of gases, such as volume, pressure, and temperature (particles are in constant random motion, no intermolecular forces, etc.) Also describes the hypothetical “ideal gas”.

an ideal gas (which is hypothetical) is defined by the following characteristics:

They’re always in random motion where they move in a straight line until they collide (with a particle or wall), the molecules are “pointe mass” they have a mass but no volume, the interactions of molecule and container are “elastic collisions” where kinetic energy is conserved. (Real gases don’t have this but they are similar)

Atmospheric Pressure is

The force that a column of air exerts on a particular area on the Earths surface (air is less compressed as you go higher up, so less pressure is exerted) Pressure is exerted in all directions to the same extent.

Standard atmospheric pressure:

760 mmHg = 1 atm = 101.325 kPa

Boyle’s Law states…

The volume of a gas varies inversely with the pressure (at a constant temperature and mass) more collisions = higher pressure (as you reduce the volume of a contained gas, there is less room for the gas particles so they collide more, basically volume goes up and pressure goes down/vice versa)

Boyle’s law equation

P₁V₁ = P₂V₂

Volume vs temperature for a gas

The temperature when the volume of a gas is zero is -273.15 Celsius (volume vs temp. of gas is linear in a graph). In 1848, Lord Kelvin suggested that is the lowest possible temperature or absolute zero.

Charles’ Law states that…

The volume of a gas varies directly with the temperature (at a constant pressure and mass). As the temperature increases, the molecules move faster, and they exert a higher pressure, which causes the volume expand.

Charle’s law formula:

^V₁/T₁ = ^V₂/T₂

Gay-Lussac’s Law states:

Pressure increases proportionally as the temperature (K) increases (assuming constant volume and mass)

Gay-Lussac’s law formula:

^P₁/T₁ = ^P₂/T₂

Combined Gas Law Calculations formula

^P₁V₁/T₁ = ^P₂V₂/T₂

STP

Standard temperature and pressure = 273.15 K (0 Celsius) and 101.325 kPa

 SATP

Standard ambient temperature and pressure = 298.15 K (25 Celsius) and 100.000 kPa

Law of Combining Volumes states…

When gases react, the volumes of the gaseous reactants and products (measured at constant temperature and pressure) are always in whole number ratios