SAT Subject Test in Chemistry

The SAT Subject Test in Chemistry assesses students' understanding of chemical concepts and their ability to apply them in problem-solving.

Atomic StructureChemical BondingStates of Matter & Gas Laws
Chemical EquilibriumAcids, Bases, and pHStoichiometry
Chemistry in MedicineEnvironmental ChemistryHousehold Chemistry
Time Management on the TestSmart Guessing and Elimination
Atomic StructureChemical BondingStates of Matter & G...Chemical EquilibriumAcids, Bases, and pHStoichiometryChemistry in Medicin...Environmental Chemis...Household ChemistryTime Management on t...Smart Guessing and E...
Basic Concepts

States of Matter & Gas Laws

The Three Main States

Matter exists as solids, liquids, or gases, and transitions between these states by gaining or losing energy.

  • Solid: Fixed shape and volume, particles vibrate in place.
  • Liquid: Fixed volume, shape adapts to container, particles slide past each other.
  • Gas: No fixed shape or volume, particles move freely and quickly.

Gas Laws

The behavior of gases can be described by several key laws:

  • Boyle's Law: \( P_1V_1 = P_2V_2 \) (at constant temperature)
  • Charles's Law: \( \frac{V_1}{T_1} = \frac{V_2}{T_2} \) (at constant pressure)
  • Ideal Gas Law: \( PV = nRT \)

These equations help predict how a gas will react to changes in pressure, volume, and temperature.

In the Real World

Understanding gas laws explains phenomena from balloon inflation to the behavior of car tires.

Summary Table

LawRelationship
Boyle’s LawPressure × Volume = constant
Charles’s LawVolume / Temperature = constant

Key Formula

\[PV = nRT\]

Examples

  • A tire inflates (volume increases) as you pump more air (increase n) into it, following the ideal gas law.

  • A balloon shrinks in the freezer because the gas inside contracts as temperature drops (Charles's Law).

In a Nutshell

Matter changes states by gaining or losing energy, and gases follow predictable laws relating pressure, volume, and temperature.

Next
Chemical Equilibrium