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HEAT UNIT. Heat Stoichiometry. Things you should know so far…. Energy transfer – endothermic vs. exothermic Energy diagrams Internal energy (including work) Heat equation Calorimetry and conservation of energy Molar enthalpy. The next big step!.
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HEAT UNIT Heat Stoichiometry
Things you should know so far… • Energy transfer – endothermic vs. exothermic • Energy diagrams • Internal energy (including work) • Heat equation • Calorimetry and conservation of energy • Molar enthalpy
The next big step! • Once you determine the molar enthalpy of reaction (or you are given it, you can put it on the correct side of the equation. • And once you’ve done that, you can treat the heat as a part of the mole ratio and do STOICH!!
Performing Heat Stoichiometry Problems • The overall reaction in commercial heat packs can be represented as: • 4 Fe(s) + 3O2(g) 2Fe2O3(s) H = -1652 kJ • a) How much heat is released when 4.00 mol of iron is reacted with excess oxygen? • b) How many moles of iron are reacted in excess oxygen to produce 533 kilojoules of energy?
Finishing up the same problem… • c) How much heat is released when 1.00 g iron is reacted with excess oxygen? • d) How much heat is released when 10.0 g of iron reacts with 2.00 g of oxygen?