1 class periods of 60 minutes each
Students will increase the concentration of salt in a solution and note when the solution goes from dilute to concentrated to saturated.
- student sheet (attached)
- 2 test tubes
- test tube rack
- graduated cylinder
Background for Teachers
This is an introductory lab to familiarize students with the vocabulary of solutions.
- If students are unfamiliar with the necessary vocabulary, create flashcards with the terms: solution, solute, solvent, concentration, percent concentration, concentrated, saturated, dilute, precipitate and dissolve. The terms will be used without definition in the lab, so it is important that they are familiar with them.
- Read the introduction and procedures to the students. Model for them the "think aloud" where as you read and come across a term you (or they) may not understand, you go to your flash card.
- Give student groups time to perform the experiment.
- Summarize class results by having students place the percent concentration of their most concentrated solution right before the precipitate formed. Salt will form about a 25% solution at room temperature. Do a class average.
- Have selected students read their conclusions to the class.
Lesson Design by Jordan School District Teachers and Staff.