Chemical Tests
Lesson 5
Exploring Water Mixtures
In lessons 3-10 students perform a series of tests to help them determine the physical and chemical properties of the five unknown chemicals.
3. Lesson set up and Management
GLE 1.1.1 Understand how to use properties to sort natural and manufactured materials and objects.
GLE 2.1.2 Understand how to plan and conduct simple investigations following all safety rules.
(345) Follow all safety rules during investigations.
GLE 2.1.5 Understand how to report investigations and explanations of objects, events, systems and processes.
(3) Report observations of simple investigations without making inferences.
Easily included:
GLE 2.2.4 Understand how to make the results of scientific investigations reliable.
- Students predict and then investigate what will happen when a greater amount of water is mixed with the unknown chemicals.
3. Lesson set up and Management
Materials:
- Use the "Check Your Science Pail" poster board for quick student reference. Add "hand lens" and "black paper."
- Signs with each material and the amount needed to be picked up at the materials center are helpful.
Students arranging and using the materials for Lesson 5
Student Management:
- Assign one partner to be the materials manager and have that student pick up the materials from the materials center after you model how to do it.
- PREPARATION #7
- Use a laminate chart like figure 5-3. It is helpful to make this chart at the beginning of the unit and have it displayed with all other test result charts.
- PROCEDURE #2
- It is helpful to show students a transparency pointing out exactly where they will be recording their information on Record Sheet 4-A.
- PROCEDRUE #5
- As students are recording their own observations on their tables carry a record sheet around, listen to their discussions, look at their written observations and record ideas from each group for class discussion during Procedure #6.
- PROCEDRUE #6
- Refer to the information you collected from the groups telling the students you gathered these from groups as they were working. Share their ideas to enhance class discussion. Many students that hesitate to share ideas out loud feel valued when they hear one of their ideas. This leads to more participation. Even though the ideas are student generated, gathering ideas as they work allows you to do quality control and focus on strong scientific observation words.
- FINAL ACTIVITIES #1
- The student trays should all be placed in the same area instead of spread around the room. This is a good chance to have a quick discussion about a control.
- FINAL ACTIVITIES #2
- Model for students what their filtration result table might look like. It is helpful to make it look like Record Sheet 4-A with only one result column.
- If you are in a real time crunch, teach this lesson on a Friday so evaporation dishes are ready to use on Monday.
Writing Support:
- Students will record their predictions and observations for what they saw during the water mixtures testing. They will also respond in their science notebooks to what they have learned by creating mixtures of unknowns and water.
Reading Support:
- Read The Magic School Bus at the Waterworks by Joanna Cole.
Math Support:
- Instead of marking the 10 ml line, allow students to practice liquid measurement on their own.
- Decide, as a class, how much time each water mixture should be stirred. Have students time the stirring using the clock.
- When sharing with the students the approximate time they will have for the activity, list the start time on the board and have them practice elapsed time by providing the approximate stop time for you to list under start time.