Heat of Solution
When ammonium chloride dissolves in water the solution becomes colder
When sodium hydroxide dissolves in water the solution heats up.
Computing Enthalpy of Solution using Lattice energy and Hydration energy for NaCl(s) -- (p 650)
- NaCl(s) ? Na+(g) + Cl-(g) - lattice energy
- Na+(g) + Cl-(g) ? Na+(aq) + Cl-(aq) hydration energy
- NaCl(s) ? Na+(aq) + Cl-(aq) - lattice energy + hydration energy
Computing Enthalpy of Solution using standard enthalpies of formation -- (p 652)
- NaCl(s) ? Na(s) + 1/2 Cl2(g) -?Hf?
- Na(s) + 1/2 Cl2(g) ? NaCl(aq, 1 m) ?Hsoln?
- NaCl(s) ? NaCl(aq, 1 m) heat = -?Hf? + ?Hsoln