Principle

Standard molar enthalpies of formation Δ_BH^Φ are important compiled thermodynamics tabulation quantities for calculating standard enthalpies of reaction for any arbitrary reaction. They are defined as the heat of reaction occurring in the direct formation of one mole of the pertinent pure substance from the stable pure elements at constant pressure. For spontaneous and quantitative formation reactions, e.g. the conversion of hydrogen and oxygen to water, standard enthalpies of formation can be measured directly using calorimetry.

Benefits

• Direct determination of standard enthalpy of formation
• Part of a system solution -  glass jacket system easily expandable

Tasks

Determine the enthalpy of formation of water by burning 100 ml H₂ in a closed glass jacket calorimeter.

Learning objectives

• First law of thermodynamics
• Thermochemistry
• Calorimetry
• Enthalpy of formation
• Enthalpy of reaction

Necessary accessories

• Precision balance 620g/0.001g