AP Chemistry question

1golfer1
Thu, 23 Apr 2015 05:00:52 +0000

6. Did your teacher explain the “half-equivalence point” concept? When half the amount of KOH necessary to reach equivalence has been added to the solution, half of the acid (HA) will have reacted. This means that at Point B on the graph, there will be equal concentrations of HA and A- (its conjugate base). Mathematically, this is shown by use of stoichometry.

7. Evaporation: Liquid --> Gas. First, you need to recognize that this is called the enthalpy of fusion energy. To vaporize a liquid, heat must be added to break the intermolecular forces between the molecules. Gasses have higher entropy than liquids (the system is more unstable / random), so the answer is A.