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Thermodynamics

Question
CBSEENCH11006190

Calculate the enthalpy change for the reaction:

CO subscript 2 left parenthesis straight g right parenthesis space plus space straight H subscript 2 left parenthesis straight g right parenthesis space rightwards arrow space space CO left parenthesis straight g right parenthesis space plus space straight H subscript 2 straight O left parenthesis straight g right parenthesis
given space that space increment straight H subscript straight f superscript degree space for space CO subscript 2 left parenthesis straight g right parenthesis comma space CO left parenthesis straight g right parenthesis space and space straight H subscript 2 straight O left parenthesis straight g right parenthesis space
are space minus 395.5 comma space minus 113.3 space and space minus 241.8 space kJ space mol to the power of negative 1 end exponent
respectively.

Solution
increment subscript straight r straight H to the power of 0 left parenthesis space for space the space reaction right parenthesis
space equals sum from blank to blank of increment subscript straight f straight H to the power of 0 left parenthesis Products right parenthesis space minus space increment straight H to the power of 0 subscript straight f left parenthesis Reactants right parenthesis
space equals space open square brackets increment subscript straight f straight H to the power of 0 left parenthesis CO right parenthesis space plus space increment subscript straight f straight H to the power of 0 left parenthesis straight H subscript 2 straight O right parenthesis close square brackets
space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space minus open square brackets increment subscript straight f straight H to the power of 0 left parenthesis CO subscript 2 right parenthesis space plus space increment subscript straight f straight H to the power of 0 left parenthesis straight H subscript 2 right parenthesis close square brackets
equals space open square brackets left parenthesis negative 113.3 right parenthesis space plus space left parenthesis negative 241.8 right parenthesis close square brackets space minus space open square brackets left parenthesis negative 395.5 right parenthesis space plus space zero close square brackets
equals space minus 355.1 space plus space 395.5 space space equals space 40.4 space kJ