Unit 5: Thermochemistry and Energy Basics

Flashcards covering key concepts and vocabulary from the thermochemistry lecture notes.

Enthalpy

The measure of heat content in a chemical reaction, represented by ΔH.

Exothermic reaction

A chemical reaction that releases heat, characterized by a negative enthalpy change.

Endothermic reaction

A chemical reaction that absorbs heat, characterized by a positive enthalpy change.

Calorimetry

A technique used to measure the amount of heat involved in a chemical or physical process.

Specific heat capacity

The quantity of heat required to raise the temperature of 1 gram of a substance by 1 °C.

Heat (q)

The transfer of thermal energy between two bodies at different temperatures.

Law of Conservation of Energy

The principle stating that energy cannot be created or destroyed, only transformed.

Potential energy

Energy stored in an object due to its position or state.

Kinetic energy

Energy possessed by an object due to its motion.

Thermal equilibrium

The state reached when two bodies in contact have the same temperature.

Heat capacity

The amount of heat absorbed or released by a substance when it experiences a temperature change.

Thermal Energy (E_th)

The total internal energy of an object due to the kinetic energy of its particles, related to temperature and phase.

Phase Energy (E_ph)

The energy stored in a substance due to its phase or state, which can be released or absorbed during phase changes, such as melting or boiling.

Heat of fusion (H_fus)

The amount of energy required to change a substance from solid to liquid at its melting point, without changing its temperature.

Heat of vaporization (H_vap)

The amount of energy needed to change a substance from liquid to gas at its boiling point, without changing its temperature.

Heat equations

q = mcΔT, q = mH

Energy Bar (LoL) graphs

A visual representation of the energy changes in a system during phase transitions, illustrating the amounts of energy absorbed or released.

Heating/Cooling curves

Graphs that show temperature changes of a substance during heating or cooling, indicating phase changes and energy absorption or release.