How to Calculate Delta H for Chemical Reactions Using Given Data and Equations?

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To calculate the delta H for the reaction 2N2 + 5O2 -> 2N2O5 using Hess's Law, the provided reactions and their enthalpy changes must be rearranged and combined. The relevant reactions include the formation of water from hydrogen and oxygen (delta H = -285.5 kJ), the formation of nitric acid from nitrogen dioxide and water (delta H = -76.5 kJ), and the formation of nitric acid from nitrogen and oxygen (delta H = -170.3 kJ). The process involves modifying these equations to match the desired reaction format, ensuring that the stoichiometry aligns correctly. Participants in the discussion emphasize the importance of demonstrating prior attempts and understanding of the concepts before seeking assistance.
bard
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calculate delta h of this eq
2N2 + 5o2 -> 2N2O5
giventhis data
h2 + 1/2o2 -> h20
and delta h of that is -285.5
n2o5 + h2o -> 2nho3 delta h -76.5
and
1/2n2 + 3/2 o2 + 1/2h2 -> hno3 delta h -170.3
 
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Are you familiar with Hess's Law? Rearrange the bottom 3 equations by modifying them and combining them to make it look like the unknown.
 
bard, you have to show what you know and have tried, before we can help you.
 

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