Chapter 11 Section 3

1. Chapter 11 Section 3 Molar heat of fusion (∆Hfus) -amount of heat required to melt one mole of a solid • endothermic= + Ex- ice cube on table -heat is absorbed

2. Molar heat of solidification (∆Hsolid) -amount of heat required to solidify one mole of a liquid -exothermic= - -same magnitude as ∆Hfus, but opposite sign b/c energy is given off ∆Hfus = -∆Hsolid -page 308 Chart 11.5

3. Molar heat of vaporization (∆Hvap) -amount of heat required to vaporize one mole of a liquid • ∆Hvapis always + (endo) b/c energy is absorbed Molar heat of condensation (∆Hcond) -amount of heat required to condense one mole of a gas to a liquid -exothermic so = - -same magnitude as ∆Hvap, but opposite sign b/c energy is given off ∆Hvap = -∆Hcond -table on page 308

4. Molar heat of solution (∆Hsolution) -the heat change caused by the dissolution of one mole of a substance *values for these will be given to you in thermochemical equation

5. Summary fusion solidliquid +∆H (endo) solidification liquid solid -∆H (exo) vaporization liquidgas +∆H (endo) condensation gasliquid -∆H (exo) solution solidaqueous ±∆H combustion burning -∆H