Penn State CHEM 113
Experiment 14 Part 1: Acid-Base Equilibria
Read through the experimental procedure in Chemtrek and watch the associated experiment videos in
Canvas. In the provided spaces, write a lab goal, summarize the procedure, record your observations,
and complete all questions included in this report sheet.
Experiment Goal. Complete before lab.
Be able to interpret conductivity experiments, investigate acid-base equilibria from bromocresol green,
determine acid dissociation equilibrium constants, use a universal indicator as a color probe to sense pH
and investigate various quantitative features of acid-base chem through titration curves.
Thompson, S. PSU Chemtrek: Expt. 14 Acid Base Equilibria; Keiser, J., Hayden-McNeil
Publishing: Plymouth, MI, 2020, pp 14-1 to 14-39.
Section A. Conductimetry and the Strength of Acids and Bases
Pre-lab data collection and observations. Complete before lab.
Using a clean conductivity probe, 6 liquid solutions are tested. Between each the leads is rinsed with
distilled water. Record whether each solution got a reading, if yes, at what level out of 10?
conductivity of various solutions
5 / 10
4 / 10
5 / 10
8 / 10
9 / 10
Arrange the six solutions tested from the lowest to the highest conductivity.
Explain the order observed
—i.e., why do solutions of the same concentration have different conductivities?
If you cannot
differentiate between them, explain why not.
The conductivity of an H
solution was followed as it was titrated with the strong base Ba(OH)
Predict the relative conductivities of:
the starting solution
the solution at the equivalence point