Activity in Chemical Equilibrium (Oxley)
- Page ID
- 281990
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Learning Objectives
After completing this exercise, students will be able to:
- Calculate the ionic strength of a solution.
- Determine the activity coefficient for species in solution.
- Perform equilibrium calculations using activity.
- Calculate the solubility of calcium oxalate, CaC2O4, in (a) water and (b) 0.050 M CaCl2. The Ksp for CaC2O4 is 1.3 x 10-8.
- Calculate the ionic strength of a solution containing 0.050 M CaCl2.
- Would an equimolar solution of NaCl or CaCl2 have a higher ionic strength? Explain.
- Calculate the solubility of calcium oxalate, CaC2O4, in 0.050 M CaCl2, including activity coefficients in your calculation. The Ksp for CaC2O4 is 1.3 x 10-8.
- What is the relative error resulting from neglecting activities in calculating the solubility of CaC2O4 in a 0.050 M solution of CaCl2?
- What is the relative error resulting from neglecting activities in calculating the pH of a 0.100 M HCl solution?
Contributors and Attributions
- Susan Oxley, St. Mary’s University (San Antonio) (soxley@stmarytx.edu)
- Sourced from the Analytical Sciences Digital Library