posted by Tori on .
ammonium nitrate decomposes to N2O and water at temperatures between 250 C and 300 C. Write a balanced chemical reaction describing the decomposition of ammonium nitrate, and calculate the standard heat of reaction using the appropriate enthalpies of formation. Please include phases. Include the steps that you took
NH4NO3 ==>N2O + 2H2O
dHrxn = (n*dHf products) - (n*dHf reactants)
When writing the equation, pay special attention to what form water takes between those temperatures.
Ammonium Nitrate is
NH₄NO₃ = -365.6 kJ/mol
N20 = +81.6 kJ/mol
H20 = -241.8 kJ/mol
Must balance decomposition equation.
Then it's products - reactants.
(Answer hint: somewhere in the ballpark of -35 kJ/mol)
Aaaahh! Don't heat it to 250C. It will explode. You will form N2O slowly heating to 170C.