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# Hess`s law watch

1. Hi,

i have to work out hess´s law form methanol and buthanol.

So far i got the formulas

2ch3oh+3o2---------2co2+4h2o

2c4h10+7o2-----------8co2+h2o

and then i am stock i do not know wjat to do
2. Would you like to clarify what you have been asked to do? Hess's Law is a concept, not a question nor a calculation. You can apply it to enable you to devise indirect ways of calculating enthalpy changes.

Your question appears to show the equations for combustion of methanol and butanol. Are you being asked to calculate these using some other data? Have you been given the enthalpy of formation of CO2, H2O and the alkanes? You can use this data to construct an indirect, hypothetical reaction route.
3. (Original post by TutorsChemistry)
Would you like to clarify what you have been asked to do? Hess's Law is a concept, not a question nor a calculation. You can apply it to enable you to devise indirect ways of calculating enthalpy changes.

Your question appears to show the equations for combustion of methanol and butanol. Are you being asked to calculate these using some other data? Have you been given the enthalpy of formation of CO2, H2O and the alkanes? You can use this data to construct an indirect, hypothetical reaction route.
I HAVE DONE AN EXPERIMENT.

i AM ATTACHING A TABLE WITH MY RESULTS

THIS IS THE QUESTION
Use Hess’s law to calculate the enthalpy changes of reaction, formation and combustion from given data.
Attached Images
4. Alcohol.pdf (19.4 KB, 12 views)

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