What is absolute zero?

Absolute zero (0 Kelvin or -273.15°C) is the theoretical temperature at which all molecular motion ceases and a gas would occupy zero volume according to Charles's Law.

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Core Study Guide

Gas Laws

The relationships between pressure, volume, temperature, and moles of gases.

Gases expand to fill container boundaries. Their physical behavior is described by mathematical gas laws.

This unit covers Boyle's Law (P-V), Charles's Law (V-T), Avogadro's Law (V-n), the Ideal Gas Law (PV=nRT), and Dalton's law of partial pressures.

Key Takeaways

•Boyle's Law: Pressure and volume of a gas are inversely proportional at constant temperature.
•Charles's Law: Volume and absolute temperature are directly proportional.
•The Ideal Gas constant (R) depends on units used for pressure.

Core Concepts & Definitions

1The Ideal Gas Law

PV = nRT. Combines individual gas laws into a single predictive equation.

•P = Pressure (atm or kPa), V = Volume (L), n = Moles.

•T = Temperature in Kelvin (K). R = 0.0821 L·atm/(mol·K) or 8.314 J/(mol·K).

Quick Revision Notes

•Gases behave most ideally at high temperatures and low pressures.
•Always convert temperature to Kelvin (K = °C + 273) before using gas formulas.