Determination of the heat of formation for CO2 and CO (Hess' law)

Principle

The standard molar enthalpies of formation Δ_BH^Φ are important compiled thermodynamic 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 pertinet pure substance from the stable pure elements at constant pressure. For spontaneous and quantitative formation reactions, e.g. the conversion of carbon and oxygen to CO₂, standard enthalpies of formation can be measured directly using calorimetry. Alternativly, the can be calculated from known entahlpies of reaction using Hess's law.

Tasks

Determine the enthalpies of reaction for the combustion of

1. carbon and
2. carbon monoxide calometrically.

Use the experimentally determined enthalpies and Hess's law to calculate the enthalpies of formation of CO and CO₂.

What you can learn about

• First law of thermodynamics
• Thermochemistry
• Calorimetry
• Enthalpy of formation
• Enthalpy of reaction
• Hess's law

Literature for this article als follows

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