Thermochemistry Review

These flashcards cover key vocabulary and concepts from the thermochemistry lecture, designed to help students prepare for their exam.

Calorimetry

The science of heat transfer in a chemical reaction.

Specific Heat Capacity

The amount of heat required to change the temperature of one gram of a substance by one degree Celsius.

ΔH

The change in enthalpy, a measure of the heat content of a system.

Hess’s Law

The principle stating that the total enthalpy change for a reaction is the sum of the enthalpy changes for individual steps, regardless of the pathway taken.

Standard Enthalpy of Formation (ΔH°f)

The enthalpy change for the formation of one mole of a compound from its elements in their standard states.

Exothermic Reaction

A reaction that releases heat, resulting in a decrease in enthalpy (ΔH is negative).

Endothermic Reaction

A reaction that absorbs heat, resulting in an increase in enthalpy (ΔH is positive).

Stoichiometry of Thermochemical Equations

The relationship between the quantities of reactants and products in a thermochemical equation, linked to the change in enthalpy.

Coffee-Cup Calorimeter

A device used to measure heat transfer at constant pressure.

Heat Transfer (q)

The flow of thermal energy from one system to another, measured typically in Joules or kilojoules.

Limiting Reagent

The reactant that is completely consumed in a reaction, determining the maximum amount of product that can be formed.

ΔHrxn

The enthalpy change associated with a specific reaction.

ΔH=Σn(products)−Σn(reactants)

A formula used in thermochemistry to calculate the enthalpy change using standard enthalpy values.