What is the molar heat of self-decomposition of nitric acid?

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The discussion centers on the molar heat of self-decomposition of nitric acid, specifically seeking the value for anhydrous nitric acid. While the exact value is not readily available online, the decomposition reaction of nitric acid is outlined as 4 HNO3(aq) -> 4 NO2(aq) + O2(g) + 2 H2O(l). It is noted that anhydrous nitric acid is rarely found in pure form due to its sensitivity to heat, shock, and light. To estimate the heat of decomposition, one can use the heats of formation for the involved compounds, suggesting a calculation approach for determining the desired value.
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I am trying to find the molar heat of self-decomposition of nitric acid.
I am curious as to what is the value of the molar heat of self-decomposition of nitric acid.

I've searched online and cannot seem to find the above value.

Essentially, I am looking for the value for anhydrous nitric acid although I am aware that the acid is generally not provided in pure form due to its sensitivity to heat, shock, and bright light.
 
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The reaction you want is 4 HNO3(aq) -> 4 NO2(aq) + O2(g) + 2 H2O(l). You can probably calculate a decent heat of decomposition using the heats of formation of the compounds involved.
 
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