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Enthalpy of Formation of CaO

Calcium metal burns according to the following equation: Ca(s) + 1/2 O2(g) --> CaO (s).
When 1.00 g of calcium metal is burned in a constant pressure calorimeter with a heat capacity of 15.20 kJ/K, the temperature increases by 1.04 degrees Celcius. Calculate the enthalpy of formation of calcium oxide. Compare this answer with -635.09 kJ/mol.

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Enthalpy of formation (DHof)is the enthalpy change when 1 mole of a substance is formed from its constituent elements in their standard states with measurements made under standard conditions of 298K and 1 atm.

The measurement of enthalpy changes of chemical and physical processes is accomplished by calorimetry. The chemical or physical process is carried out on a precisely known scale in an insulated container called a calorimeter.
The insulation prevents the flow of heat from the surroundings to the system (inside the calorimeter) ...

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