Concept explainers
Interpretation: The additional data required to determine the
Concept introduction:
Chemical reactions proceed with the absorption (endothermic) or evolution (exothermic) of heat.- Enthalpy change or the change in the energy of a chemical reaction can be deduced in terms of the enthalpy of formation of the products and reactants.
- The enthalpy of formation of any chemical system in its natural state is zero.
Answer to Problem 9.95PAE
Solution: The data showing the standard enthalpy of formation of solid silicon dioxide is required.
Explanation of Solution
The given reaction is:
Reaction enthalpy can be calculated using the following equation
nproducts and nreactants are the number of moles of products and reactants respectively
Based on equation (1) for the given reaction we can write:
Therefore,
The standard enthalpy of formation of solid silicon dioxide is required to calculate the enthalpy of formation of silicon nitride.
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Chapter 9 Solutions
CHEM FOR ENGNRNG SDNTS (EBOOK) W/ACCES
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