posted by Jen on .
1) The specific heat of solid copper is 0.385 J/g(C). What thermal energy change occurs when the temperature of a 34.10 g sample of copper is cooled from 35.7 degrees Celsius to 13.9 degrees Celsius?
Answer: -286.3 J
This amount of heat is used to melt solid ice at 0.0 degrees Celsius. The molar heat of fusion of ice is 6.00 kJ/mol. How many moles of ice are melted?
2) Brazilians are quite familiar with fueling their automobiles with ethanol, a fermentation product from sugarcane. Calculate the standard molar enthalpy for the complete combustion of liquid ethanol (C2H5OH) using the standard enthalpies of formation of the reactants and products.
C2H5OH(l) + 3O2(g) --> 2CO2(g) + 3H2O(g)
q = mass x specific heat x (Tfinal-Tinitial)
Write the equation and balance it.
deltaHfrxn = (n*DHfproducts)-(n*DHfreactants)
You can find the delta Hf products and reactants in your text or notes.