1. Chem 1310: Introduction to physical chemistry Part 3: Equilibria Writing K expressions

2. Write out the chemical equation. Write out the K expression using concentrations whenever possible. Initially include all components, including solids etc. Then remove the pure solids, pure liquids and "nearly-pure" solvents.

3. Dissociation of an acid in water HNO 2 in water

4. Dissociation of an acid in water HNO 2(aq) + H 2 O ⇋ NO 2 - (aq) + H 3 O + (aq)

5. Dissociation of an acid in water HNO 2(aq) + H 2 O ⇋ NO 2 - (aq) + H 3 O + (aq)

6. Dissociation of an acid in water HNO 2(aq) + H 2 O ⇋ NO 2 - (aq) + H 3 O + (aq)

7. Dissolving a salt in water NaCl (s) ⇋ Na + (aq) + Cl - (aq)

8. Dissolving a salt in water NaCl (s) ⇋ Na + (aq) + Cl - (aq)

9. Evaporation of a solid I 2(s) ⇋ I 2(g)

10. Evaporation of a solid I 2(s) ⇋ I 2(g)

11. Dissolving a gas in water CO 2(g) ⇋ CO 2(aq)

12. Dissolving a gas in water CO 2(g) ⇋ CO 2(aq)

13. Dissolving a liquid in water Br 2(l) ⇋ Br 2(aq)

14. Dissolving a liquid in water Br 2(l) ⇋ Br 2(aq)