1. The standard enthalpy of formation of phenol is -165.0 kJ/mol. Calculate its standard enthalpy of combustion. [Express your answer in units of kilojoules per mole, kJ/mol]
C6H5OH + 7O2 --> 6 CO2 + 3H2O
ΔHc = 6ΔHf(CO2) + 3ΔHf(H2O) - ΔHf(C6H5OH) - 7ΔHf(O2)
2. Calculate the work done on a closed system consisting of 50.0 grams of argon, assumed ideal, when it expands isothermally and reversibly from a volume of 5.00 L to a volume of 10.00 L at a temperature of 298 K. [Express your answer in units of kiloJoules, kJ]
w = -nRT ln(V2/V1)
3. The heat capacity of a substance is often reported in the form Cp,m = a + bT + c/T2. Use this expression to make a more accurate estimate of the change in molar enthalpy of carbon dioxide when it is heated from 15°C to 37°C, given a = 44.22 J K−1 mol−1, b = 8.79 × 10−3 J K−2 mol−1, and c = −8.62 × 105 J K mol−1. Give your answer in the units of J/mol.
dH = CpdT.
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