Take Home Lab #8

Take Home Lab #8: Solubility Lab

Question: Which household substances are polar and which are nonpolar?

Safety: Keep the cups out of reach of children so they do not drink the solutions. Do not consume any of the materials. Use caution when working with rubbing alcohol; it is flammable. Keep away from all flames and/or spark sources. Immediately wipe up any liquid spilled on the floor.

Materials: cups, oil, water, rubbing alcohol, salt, sugar, baking soda

Procedure: In this lab, you will figure out which solids are soluble in which liquids. For the liquids, you will use water, rubbing alcohol, and cooking oil. For the solids, you will use salt, sugar, and baking soda. In the end, you will see if the liquids will mix together. This will help you answer the questions about which solutes are solvents are polar.

            In a small cup, try the following combinations to see if the solute will dissolve in the solvent. Stir the solutions and allow at least 60 seconds for the solutes to dissolve. Be sure to clean the cups with dishwashing liquid between each use.

            1. water and salt

            2. water and sugar

            3. water and baking soda

            4. rubbing alcohol and salt

            5. rubbing alcohol and sugar

            6. rubbing alcohol and baking soda

            7. cooking oil and salt

            8. cooking oil and sugar

            9. cooking oil and baking soda

            10. cooking oil and water

Post-Lab Questions:

1. Make a chart showing whether each substance dissolved or not. Or mixed or not.

2. In general, polar items dissolve other polar items and nonpolar items dissolve nonpolar items. Water is polar. Which of the solids are polar?

3. In general, polar liquids mix with other polar liquids, and vice versa. Which of the liquids are polar?

4. From your experience, is antifreeze (for the car, like ) polar? Epsom salts? Car oil? Animal fat? Artificial sweetener (such as Nutrasweet or Splenda)? Sand?