Unformatted text preview: Consider the reaction CH 4 (g) + X 2 (g) → CH 3 X(g) + HX(g) , where X is a halogen-like atom (Group 7A). Calculate Δ H for this reaction if bond en-ergy tables give the following values: C H : 416 kJ/mol X X : 235 kJ/mol H X : 322 kJ/mol C X : 258 kJ/mol Correct answer: 71 kJ / mol. Explanation: C H H H H + X X----→ C X H H H + H X Δ H rxn = s BE rct-s BE prod = b 4 (C H) + (X X) B-b 3 (C H) + (C X) + (H X) B = b (C H) + (X X) B-b (C X) + (H X) B = b (416 kJ / mol) + (235 kJ / mol) B-b (258 kJ / mol) + (322 kJ / mol) B = 71 kJ / mol 010 (part 1 of 1) 10 points Which of the following would probably have a positive Δ S value?...
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This note was uploaded on 01/23/2011 for the course CH 301 taught by Professor Fakhreddine/lyon during the Spring '07 term at University of Texas.
- Spring '07