Understand standard enthalpy changes of combustion,Hc, and formation, Hf. Deduce equations and solutions to problems involving these terms.
Calculate enthalpy changes of a reaction using Hfdata or Hcdata:
Understand a Born-Haber cycle for an ionic compound. Interpret and determine values from a Born-Haber cycle for compounds composed of univalent and divalent ions, including: ionization energies, enthalpy of atomization, electron affinities, lattice enthalpy, enthalpy of formation. The construction of a complete Born-Haber cycle will not be assessed.
Entropy and Spontaneity (HL)
Define entropy,S, as a measure of the dispersal or distribution of matter and/or energy in a system. Predict whether a physical or chemical change will result in an increase or decrease in entropy of a system. Calculate standard entropy changes, S, from standard entropy values,S.
Understand the change in Gibbs energy, G, relates the energy that can be obtained from a chemical reaction to the change in enthalpy, H, change in entropy, S, and absolute temperature,T. Apply the equation G= H- TSto calculate unknown values of these terms.
Interpret the sign of Gcalculated from thermodynamic data. Determine the temperature at which a reaction becomes spontaneous.