AP Chemistry Gas Laws and States of Matter

Flashcards covering key terms, definitions, laws, and concepts related to states of matter and ideal gas laws, based on lecture notes.

Molecular Solid

A type of solid characterized by a relatively low melting point.

Metals (Conductivity)

Substances that conduct electricity in their solid state, such as copper.

Covalent Network Solid

A type of solid with a high melting point and no electrical conductivity.

Ionic Solid (Conductivity)

A solid that conducts electricity when in an aqueous solution or molten, as it separates into ions.

Solids

A state of matter characterized by retaining shape and volume, being virtually incompressible, having crystalline shapes, and tightly packed, vibrating particles with strong intermolecular forces.

Liquids

A state of matter that retains volume but takes the shape of its container, has more disorganized but still tightly packed particles that slip and slide past each other, allowing flow, and is virtually incompressible.

Gases

A state of matter where particles are far apart, take the entire space and shape of their container, are constantly moving randomly, have lots of empty space (compressible), and have negligible intermolecular forces.

Absolute Zero

The theoretical temperature (0 Kelvin) at which all particle motion is speculated to stop.

Water Density Exception

Solid water (ice) is less dense than liquid water because its particles are further apart due to the arrangement of intermolecular forces in the solid phase.

Evaporation

The process by which some liquid particles at the surface enter the gas phase, even if the liquid is not at its boiling point.

Gas Molecules (Phase Change)

During a phase change to gas, individual molecules remain intact (e.g., H2O remains H2O); only the intermolecular forces between molecules are overcome, not the molecules themselves.

Pressure (P)

The force exerted per unit area, generated by the collisions of gas particles with the walls of the container, proportional to particle velocity and collision frequency.

Standard Pressure (STP)

A specific condition for pressure, defined as one atmosphere (1 atm).

AP Chemistry Pressure Units

The accepted units for pressure in AP Chemistry are atmospheres (atm), millimeters of mercury (mmHg), and Torr.

Temperature (T)

A measure of the average kinetic energy (energy of motion) of a substance's particles.

Standard Temperature (STP)

A specific condition for temperature, defined as zero degrees Celsius (0 °C) or 273 Kelvin (273 K).

Temperature Calculation Requirement

Temperature must always be converted and used in Kelvin for all gas law calculations.

Kelvin to Celsius Conversion

The formula used to convert Celsius to Kelvin is K = °C + 273 (or 273.15).

Moles (n)

The unit representing the amount of gas present.

Volume (V)

The amount of space occupied by a substance; gases always take on the volume and shape of their container.

Volume Conversion (mL to L)

The conversion factor for volume is 1 Liter (L) = 1000 milliliters (mL).

Cubic Centimeter (cc)

An alternative unit for volume, equivalent to one milliliter (1 mL), often used in medical contexts.

Molar Volume at STP

One mole of any ideal gas at Standard Temperature and Pressure (STP) occupies 22.4 liters (L).

Combined Gas Law

An equation relating pressure, volume, and temperature of a gas: P1V1/T1 = P2V2/T2, used when comparing two states of the same gas.

Boyle's Law

States an inverse relationship between pressure and volume of a gas at constant temperature and moles (P1V1 = P2V2).

Gay-Lussac's Law

States a direct relationship between temperature and pressure of a gas at constant volume and moles (P1/T1 = P2/T2).

Charles's Law

States a direct relationship between temperature and volume of a gas at constant pressure and moles (V1/T1 = V2/T2).

Avogadro's Law

States that equal volumes of gases at the same temperature and pressure contain equal numbers of moles, showing a direct relationship between volume and moles (V1/n1 = V2/n2).

Ideal Gas Law

An equation that describes the relationship between pressure, volume, moles, and temperature for an ideal gas: PV = nRT.

Ideal Gas Constant (R)

The proportionality constant in the Ideal Gas Law (PV=nRT), with a value of 0.08206 L·atm/(mol·K).

Molar Mass (Gas Laws)

Used in gas law calculations where moles (n) can be found by dividing the mass (m) of the gas by its molar mass (M): n = m/M.