Gas Laws Flipbook

Gas Laws Flipbook

By: Abhay Bindroo 1A

Kinetic Molecular Theory

Gas Particle Behavior and Motion

• Paticles move in constant, random motion
• Collisions between particles are perfectly elastic
• Volume of gas particles in negligible
• Average Kinetic Energy of molecules is its Kelvin temperature
• Theory assumes no intermolecular forces between the particles
• Gases expand to fill container unlike solids/liquids
• Gases are very compressible unlike solids/liquids

To summarize, this theory tells us that gas paricles are always moving, kinetic energy is conserved, volume of the particles doesn't really matter because they are very small, and that Kelvins tell us the average kinetic energy of the molecules assuming that no intermolecular forces act between the particles.

Volume, Temperature, and Pressure

Volume (V)

• Definition: The amount of 3-dimensional space occupied by a liquid, solid, or gas.
• Units: L (liters)
• Conversion Methods: 1L = 1000 mL

Temperature (T)

• Definition: Temperature is the property of matter which reflects the quantity of energy of motion of the component particles.
• Units: K (Kelvins)
• Conversion Methods: K = C + 273 (C is celsius)

Pressure (P)

• Definition: Determined by the flow of a mass from a high pressure region to a low pressure region; a measure of the force that a gas exerts on its container.
• Units: atmospheres/Pascals (N/m^2)
• Conversion Methods: 1 atm = 101.3 kPa = 760 mm Hg = 760 torr = 29.92 Hg = 14.7 psi = 10^5 Pa; Gas pressure = atmospheric pressure + or - h (depending on the difference in mercury levels)

Ideal Gas Law

Definition: A description of gas behavior that permits you to solve for the number of moles of a contained gas when given only ONE VALUE EACH for P, V, and TRelated Variables

• Pressure (P)
• Volume (V)
• Temperature (T)
• n (moles of gas)

Constant Variables

• R (Ideal Gas Constant: depends on pressure unit!)
• 0.0821 L*atm/mol*K
• 8.31 L*kPa/mol*K
• 62.4 L*mmHg/mol*K

Equation: PV = nRT

Avogadro's Principle/Molar Volume

Definition: This is the volume (22.4 L) that one mole of gas occupies at STP STP

• Standard Temperature (273K/0C)
• Standard Pressure (101.3kPa/1atm)

Conversion Factor: 22.4 L = 1 mol at STP for gases

• If Pressure and Temperature are held constant at STP....

Boyle's Law

Graphic Representation:

Definition: The volume of a confined gas is inversely proportional to the pressure exerted on the gas

• All gases behave this way!

Related Variables

• Pressure (P)
• Volume (V)

Constant Variables

• Temperature (T)
• Product of Pressure and Volume at a Constant Temperature (PV)

Formula: P1V1 = P2V2

• Holds true only at low pressures!

Charle's Law

Definition: If a given quantity of gas is held at a constant pressure, then its volume is directly proportional to the absolute temperature.

• Must use Kelvins!

Related Variables

• Temperature (T)
• Volume (V)

Constant Variables

• Pressure (P)

Formula: V1T2 = V2T1 OR V1/T1 = V2/T2

Graphic Representation:

Gay-Lussac's Law

Definition: Volumes of Gases always combine with one another in the ratio of small whole numbers, as long as the volumes are measured at the same T and PRelated Variables

• Temperature (T)
• Pressure (P)

Constant Variables

• Volume (V)

Formula: P1T2 = P2T1 OR P1/T1 = P2/T2

• If pressure increases (and the container is not exapandable), the temperature increases

Graphic Representation:

Combined Gas Law

Definition: Demonstrates what happens to one variable if two of the other variables change using a combination of the Boyle's, Charle's, and Gay-Lussac's laws

• You can use this law to find the equations for all the other laws!

Related Variables

• Temperature (T)
• Pressure (P)
• Volume (V)

Constant Variables

• Ideal Gas Constant (R)
• As long as the pressure units are the same!
• Moles (n)

Formula: P1V1/T1R1 = P2V2/T2R2