chemistry

posted by .

How much heat is evolved or absorbed in this problem?
Question Details
Limestone, CaCo3, when subjected to a temperature of 900 degrees Celsius in a kiln, decomposes to calcium oxide and carbon dioxide. How much heat is evolved or absorbed when one gram of limestone decomposes?

The standard enthalpies of formation at 25 degrees Celsius(kj/mol) of these compounds at 1 atm, Aqueous ions at 1 M is:

CaCO3 -1206.9
CaO -635.1
CO2 -393.5

• chemistry -

Nitroglycerin is a powerful explosive, giving four different gases when detonated.2 C3H5(NO3)3 (l) → 3 N2 (g) + 1/2 O2 (g) + 6 CO2 (g) + 5 H2O (g)Given that the enthalpy of formation of nitroglycerin, ΔHf°, is −364 kJ/mol, calculate the energy (heat at constant pressure) released by this reaction.Δ= Σn􀁄rxnHfΔ􀁄H(prod.) − ΣmfΔ􀁄H(reac.)= (3 mol)(0) + (1/2 mol)(0) + (6 mol)(−393.5 kJ/mol) + (5 mol)(−241.8 kJ/mol) − (2 mol)(−364 kJ/mol) rxnΔ􀁄H= −2842 kJ rxnΔ􀁄Hb) What is delta H when 4.65 mol of products is formed?

• to ogi--chemistry -

• chemistry -

dHrxn = (n*dH products) - (n*dH reactants)