2. Explain the effect of each of the following sources of error on the molarity of NaOH as determined in this experiment stating whether the concentration of NaOH obtained would be too high or too low.
a. The buret is contaminated with an acid solution.
b. The buret contains a large air bubble in the tip, which disappears in the course of the titration.
c. A small volume of the acid solution is spilled when you transfer it into the Erlenmeyer flask.