9.6. Formaldehyde may be produced in the reaction between methanol and oxygen: 2CH3OH(1) + O2(g) → 2HCHO(g) + 2H2O(1): AH; = –326.2 kJ The standard heat of combustion of hydrogen is H2(g) +O2(g) → H;O(1): AĤ, = -285.8 kJ/mol (a) Use these heats of reaction and Hess's law to determine the standard heat of the direct decomposition of methanol to form formaldehyde: CH;OH(1) → HCHO(g) + H2(g) (b) Explain why you would probably use the method of Part (a) to determine the heat of the methanol decomposition reaction experimentally rather than carrying out the decomposition reaction and measuring AH, directly.

9.6. Formaldehyde may be produced in the reaction between methanol and oxygen: 2CH3OH(1) + O2(g) → 2HCHO(g) + 2H2O(1): AH; = –326.2 kJ The standard heat of combustion of hydrogen is H2(g) +O2(g) → H;O(1): AĤ, = -285.8 kJ/mol (a) Use these heats of reaction and Hess's law to determine the standard heat of the direct decomposition of methanol to form formaldehyde: CH;OH(1) → HCHO(g) + H2(g) (b) Explain why you would probably use the method of Part (a) to determine the heat of the methanol decomposition reaction experimentally rather than carrying out the decomposition reaction and measuring AH, directly.

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter5: Thermochemistry

Section: Chapter Questions

Problem 5.86QE: One of the components of jet engine fuel is n-dodecane, C12H26(), which has a standard enthalpy of...

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