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

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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