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Grade 11 Chemistry ExampleThis example shows how you might approach the concept of solutions, dilution, and titration using a flipped model. This series of lessons was delivered in three 80-minute lessons with associated homework.
Pre-activites (Homework): Students watch the video (on the left) from the beginning up to 5:30. Once (or as) they watch, they are asked to try the 4 example calculations (left) similar to what they saw in the video. The examples are worked through at the end of the document so they can see if they are working correctly. |
In class:
1. Starter activity: To see if students understood the video content and could work through the examples,ask students to solve the following:
Starter question:
If 0.500 dm3 of a solution of LiBr has a concentration of 0.75 mol dm-3, how many grams of solute are in the solution?
A. 0.75
B. 87
C. 0.38
D. 33
Before telling them the correct answer, do a quick check of their answers (by having students hold up lettered cards or using a tool like Socrative). If there is a wide range of answers, ask the students to find someone who had a different answer than they did and then have them work through to help each other. Do another quick check. If most students are correct, move on. If not, work through the question with them, or ask one student to work through their answer on the board.
2. Putting the knowledge into action: Students complete part 1 of the following Solutions Lab (Making a solution). This puts their knowledge into a context. The attached document has 9 different versions so student pairs will make different solutions.
1. Starter activity: To see if students understood the video content and could work through the examples,ask students to solve the following:
Starter question:
If 0.500 dm3 of a solution of LiBr has a concentration of 0.75 mol dm-3, how many grams of solute are in the solution?
A. 0.75
B. 87
C. 0.38
D. 33
Before telling them the correct answer, do a quick check of their answers (by having students hold up lettered cards or using a tool like Socrative). If there is a wide range of answers, ask the students to find someone who had a different answer than they did and then have them work through to help each other. Do another quick check. If most students are correct, move on. If not, work through the question with them, or ask one student to work through their answer on the board.
2. Putting the knowledge into action: Students complete part 1 of the following Solutions Lab (Making a solution). This puts their knowledge into a context. The attached document has 9 different versions so student pairs will make different solutions.
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Homework: Watch video from 5:30 until the end. Make your own notes and try this example:
What volume of 1.5 mol dm-3 HCl is needed to make 250.0 cm3 of a 0.10 mol dm-3 solution of HCl? (Answer: 0.017 dm3 or 17 cm3)
In class:
1. Starter Activity: Similar set up to the previous lesson, but use 2 questions this time.
Dilution starter question #1:
A solution of LiBr has a concentration of 0.75 mol dm-3. What volume of this solution is needed to make 250.0 cm3 of a 0.20 mol dm-3 solution?
A. 67 cm3
B. 67 dm3
C. 940 cm3
D. 0.050 dm3
Dilution starter question #2:
A 0.500 dm3 solution of LiBr has a concentration of 0.038 mol dm-3. How much water was added to make a 0.010 mol dm-3 solution?
A. 1.9 dm3
B. 1.4 dm3
C. 0.028 dm3
D. 0.13 dm3
2. Putting the knowledge into action: Students complete Part 2 of the Solutions Lab (Doing a dilution).
What volume of 1.5 mol dm-3 HCl is needed to make 250.0 cm3 of a 0.10 mol dm-3 solution of HCl? (Answer: 0.017 dm3 or 17 cm3)
In class:
1. Starter Activity: Similar set up to the previous lesson, but use 2 questions this time.
Dilution starter question #1:
A solution of LiBr has a concentration of 0.75 mol dm-3. What volume of this solution is needed to make 250.0 cm3 of a 0.20 mol dm-3 solution?
A. 67 cm3
B. 67 dm3
C. 940 cm3
D. 0.050 dm3
Dilution starter question #2:
A 0.500 dm3 solution of LiBr has a concentration of 0.038 mol dm-3. How much water was added to make a 0.010 mol dm-3 solution?
A. 1.9 dm3
B. 1.4 dm3
C. 0.028 dm3
D. 0.13 dm3
2. Putting the knowledge into action: Students complete Part 2 of the Solutions Lab (Doing a dilution).
Homework: Students watch a video showing the technique of titration. This will eliminate the need for a demonstration in class and students can use maximum time to practice the technique.
In class: Discuss any questions from the video and have students complete Part 3 of the Solutions Lab. I usually have them titrate another group's solution with the label removed so they don't know which group they have or which concentration. Their challenge is to titrate correctly to get the correct concentration. I usually have students do one practice trial and then one real trial as this is all there is time for. If time, have students complete more trials. |
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Summary: This series of lessons has worked well. Students have learned how to calculate concentrations through seeing examples, and then doing the calculations in the context of making the solution. They collaborate and help each other, and giving them a different solution to titrate puts in an element of competition that has motived students.