Question from OCR A Student Book: 9.3 Summary Questions
Use Table 1 and the following data:
2SO2(g) + O2(g) → 2SO3(g) ΔH= -192kJmol-1
Assume that SO2 and SO3 contain only S=O bonds a) Calculate the average bond enthalpy for the S=O bond. b) The actual bond enthalpy for the S=O bond in SO2 is 531kJmol-1. Calculate the actual bond enthalpy for the S=O bond in SO3.
Question from OCR A Student Book: 9.3 Summary Questions
Use Table 1 and the following data:
2SO2(g) + O2(g) → 2SO3(g) ΔH= -192kJmol-1
Assume that SO2 and SO3 contain only S=O bonds a) Calculate the average bond enthalpy for the S=O bond. b) The actual bond enthalpy for the S=O bond in SO2 is 531kJmol-1. Calculate the actual bond enthalpy for the S=O bond in SO3.
Table 1:
What have you tried/what specifically is causing trouble in answering this question?
What have you tried/what specifically is causing trouble in answering this question?
By using the equation, I found that 2SO2 has 4(S=O) bonds, O2 has 1 (O=O) and 2SO3 has 6 (S=O), Since (O=O) is 498 and the Enthalpy change is -192 I set up an equation: 4(S=O) + (O=O) —> 6(S=O) 4(S=O) + 498 – 6(S=O) = –192kJmol-1
By rearranging: 690 = 2(S=O) 345 = (S=O)
However the answer to the questions in the book is 469 which doesn't show working out. I know the book has many mistakes with answers so I'm not sure if I'm completely off the mark or if there's something wrong with the books answer.
Since I'm not sure about question a, I really don't know how to go about answering b)
By using the equation, I found that 2SO2 has 4(S=O) bonds, O2 has 1 (O=O) and 2SO3 has 6 (S=O), Since (O=O) is 498 and the Enthalpy change is -192 I set up an equation: 4(S=O) + (O=O) —> 6(S=O) 4(S=O) + 498 – 6(S=O) = –192kJmol-1
By rearranging: 690 = 2(S=O) 345 = (S=O)
However the answer to the questions in the book is 469 which doesn't show working out. I know the book has many mistakes with answers so I'm not sure if I'm completely off the mark or if there's something wrong with the books answer.
Since I'm not sure about question a, I really don't know how to go about answering b)
By using the equation, I found that 2SO2 has 4(S=O) bonds, O2 has 1 (O=O) and 2SO3 has 6 (S=O), Since (O=O) is 498 and the Enthalpy change is -192 I set up an equation: 4(S=O) + (O=O) —> 6(S=O) 4(S=O) + 498 – 6(S=O) = –192kJmol-1
By rearranging: 690 = 2(S=O) 345 = (S=O)
However the answer to the questions in the book is 469 which doesn't show working out. I know the book has many mistakes with answers so I'm not sure if I'm completely off the mark or if there's something wrong with the books answer.
Since I'm not sure about question a, I really don't know how to go about answering b)
U create an equation as well Using the actual bond enthalpy of s-o in so2 which is 531kjmol find the total 4(o-s-o)= 2124 = 2124+498-6x=-192 =2124+498+192=6x =2814=6x =2814/6= 469kjmol
U create an equation as well Using the actual bond enthalpy of s-o in so2 which is 531kjmol find the total 4(o-s-o)= 2124 = 2124+498-6x=-192 =2124+498+192=6x =2814=6x =2814/6= 469kjmol
thank you! this is so helpful i actually understand the qs now🙂