Aqueous Chemistry
1. You have been assigned a chemical and a Ksp. Calculate the molar solubility. Show all work, equations, and relevant calculations. (15 points)
2. You have been assigned a solution and a volume. Calculate the molarity and the molality. How would a cell behave in this solution? (15 points)
3. You have been assigned a colligative property. Provide an authentic context in which this colligative property makes sense. Walk through a calculation to determine the impact of the assigned colligative property. (15 points)
4. Create a venn diagram for the solubility of ions. Which are most soluble? Which are least soluble? Please refer to the solubility rules. (15 points)
Collaborative Questions (40 points total)
1. Using water activity, create guidelines for how packaged food should be stored. (10 points)
2. Solubility “rules” are often used to describe the behavior of chemical compounds in water. Using the table below and your knowledge of solubility (Ksp) create three examples of molar solubility to explain what makes a chemical soluble or insoluble.
| Term | range | example | g/dL |
| Very soluble | <1 | Calcium nitrate | |
| Freely soluble | 1 to 10 | Calcium chloride | |
| Soluble | 10 to 30 | Sodium oxalate | |
| Sparingly soluble | 30 to 100 | ||
| Slightly soluble | 100 to 1000 | Calcium sulfate | |
| Very slightly soluble | 1000 to 10,000 | Dicalcium phosphate | |
| Practically insoluble or insoluble | >=10,000 | Barium sulfate |
Here, range refers to the part of the solvent required per part of the solute. (15 points)
Answer
3. Osmolality of cell culture media can also be used as an indicator of cell viability. The osmolality of the host cell culture medium can affect the composition of the viral membranes produced, which in turn, affects the stability of the vectors in the final gene therapy products. The osmolality of the buffer solution used with viral vectors can also directly affect viral stability. Assume you are working with a buffer including a 10% sodium hydrogen phosphate (NaH2PO4) solution. What is the osmolality of this solution? (15 points)
