1) The first step in the production of high purity silicon for semiconductors is represented by this equation. Sio:(s) + 2C(s) → Si(s) + 2CO(g) AH° = +689.9 kJ a. Calculate AH for SiO2(s). Given: AH° for CO(g) = -110.5 kJ-mol1 b. Find ASpn for the production of pure silicon. Given: S° for C(s) = 5.7 J-K-1-mol-1, for CO(g) is 197.6 J-K-1-mol-1, for Si(s) = 18.8 J-K-1-mol-1, and for SiO2(s) = 41.8 J-K-1-mol-1 c. Determine AG° for the reaction at 25 °C. d. Find the minimum temperature in °C at which this reaction is spontaneous. Assume that AH° and AS° do not vary with temperature.

1) The first step in the production of high purity silicon for semiconductors is represented by this equation. Sio:(s) + 2C(s) → Si(s) + 2CO(g) AH° = +689.9 kJ a. Calculate AH for SiO2(s). Given: AH° for CO(g) = -110.5 kJ-mol1 b. Find ASpn for the production of pure silicon. Given: S° for C(s) = 5.7 J-K-1-mol-1, for CO(g) is 197.6 J-K-1-mol-1, for Si(s) = 18.8 J-K-1-mol-1, and for SiO2(s) = 41.8 J-K-1-mol-1 c. Determine AG° for the reaction at 25 °C. d. Find the minimum temperature in °C at which this reaction is spontaneous. Assume that AH° and AS° do not vary with temperature.

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter8: Thermochemistry

Section: Chapter Questions

Problem 87QAP: The thermite reaction was once used to weld rails: 2Al(s)+Fe2O3(s)Al2O3(s)+2Fe(s)(a) Using heat of...

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