For this week we will be going back to the Home Scientist labs.
Reading: Topic II. Solubility and Solutions. We will be doing Session II-1. Solubility as a Function of Temperature pp. 42-52.
Experimental Title: Lab 16: Solubility as a Function of Temperature
Date of laboratory: September 16, 2014
Purpose: The purpose of this laboratory is to examine solubility of solid solutes as a function of temperature.
Go ahead and read through his introduction, pp. 42- 45, which covers some of the same things as the lesson and text readings. Briefly summarize the background information from the lab as for your own lab notebook introduction. The background information can be found on pp. 46-47.
Special safety concerns for Lab 16:
- If anything spills, please clean it up immediately with a paper towel and let your instructor know.
- If glass breaks, do not pick it up with your bare hands. Notify your instructor immediately.
- Be careful with the hot solution.
- Be sure to wash your hands when you are finished with this lab
Materials: See lists page 46.
You will find the process is somewhat similar to the recrystallization lab we did earlier. To help speed things up, I will be doing some of the preparation work for you ahead of time.
Part I. The synthesis of sodium carbonate, page 48 – 49: I will do this at home and bring the sodium carbonate to lab already prepared. Go ahead and start with part II in your lab notebook, but be aware that we are working with washing soda and not baking soda.
Part II. Calibrate your thermometer.
Part III. Determine the solubility of sodium carbonate
We have the electronic scale, so we don’t need to worry about the conversions he lists in the note at the bottom of page 50. You can skip that part.
Note: Several time he says “stir gently with the thermometer.” Please use a stirring rod instead.
Be sure to leave room in your notebook for the graph. It should look something like this:
Once you have completed the lab, sit down and write a sentence or two to explain the results.
Record any thoughts you have about the experiments, including:
- Possible improvements to the procedures or how to tweak techniques
- How the results differed from your expectations
- Suggestions for other experiments
- What key concepts you learned
(Image public domain)
Please leave a comment or send an e-mail if you have any questions before our meeting.