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Question
Define the Standard enthalpy of combustion.
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Solution
The standard enthalpy of combustion of a substance is the standard enthalpy change accompanying a reaction in which one mole of the substance in its standard state is completely oxidised.
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Calculate C – Cl bond enthalpy. The bond enthalpies are:
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| ∆H°/kJ mol−1 | 414 | 243 | 431 |
Calculate the standard enthalpy of formation of liquid methanol from the following data:
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The volume of oxygen required for complete combustion of 0.25 mole of methane at STP is ______.
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The enthalpy change accompanying a reaction in which 1 mole of the substance in the standard state reacts completely with oxygen or is completely burnt is called as ____________.
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Calculate the standard enthalpy of formation of CH3OH(l) from the following data:
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C = C bond energy: 606.10 kJ mol−1
C – C bond energy: 336.49 kJ mol−1
C – H bond energy: 410.50 kJ mol−1
Enthalpy for the given reaction will be:
\[\begin{array}{cc}
\phantom{}\ce{H}\phantom{...}\ce{H}\phantom{...................}\ce{H}\phantom{...}\ce{H}\phantom{....}\\
\phantom{.}|\phantom{....}|\phantom{....................}|\phantom{....}|\phantom{.....}\\
\ce{C = C + H - H -> H - C - C - H}\\
\phantom{.}|\phantom{....}|\phantom{....................}|\phantom{....}|\phantom{.....}\\
\phantom{}\ce{H}\phantom{...}\ce{H}\phantom{...................}\ce{H}\phantom{...}\ce{H}\phantom{....}
\end{array}\]
The enthalpy change that accompanies a reaction in which 1 mole of its standard state is formed from its elements in their standard states
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Calculate ΔsubH of the H2O from the given data:
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