Concept explainers
Interpretation:
The standard enthalpy of formation of
Concept Introduction:
The measure of stability of molecule is bond enthalpy. The change in enthalpy is related in breaking a specific bond of 1 mole of gaseous molecule. In solids and liquids bond enthalpies are affected by neighboring molecules. There is possibility to predict the enthalpy of reaction using the average bond enthalpies. Energy is always needed for the breaking of
The enthalpy of reaction in gas phase is given by,
Where,
BE= Bond enthalpy and
Standard enthalpy of formation:
The change in enthalpy that is associated with the formation of one mole of a substance from its related elements being in standard state is called standard enthalpy of formation (
The standard enthalpy of reaction is the enthalpy of reaction that takes place under standard conditions.
The equation for determining the standard enthalpies of compound and element can be given by,
To calculate: The
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Chemistry: Atoms First
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- Using the bond dissociation enthalpies in Table 8.8, estimate the enthalpy of combustion of gaseous methane, CH4, to give water vapor and carbon dioxide gas.arrow_forwardUsing the standard enthalpy of formation data in Appendix G, calculate the bond energy of the carbon-sulfur double bond in CS2.arrow_forwardDinitrogen monoxide, N2O, can decompose to nitrogen and oxygen gas: 2 N2O(g) 2 N2(g) + O2(g) Use bond dissociation enthalpies to estimate the enthalpy change for this reaction.arrow_forward
- The bond energy for a CH bond is about 413 kJ/mol in CH4 but 380 kJ/mol in CHBr3. Although these values are relatively close in magnitude, they are different. Explain why they are different. Does the fact that the bond energy is lower in CHBr3, make any sense? Why?arrow_forwardhat is the enthalpy change for a process? Is enthalpy a state function? In what experimental apparatus are enthalpy changes measured?arrow_forwardExplain the decomposition of nitroglycerin in terms of relative bond enthalpies.arrow_forward
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