Lesson 1 - Monday, Oct 16
Focus Question: What causes the bubbling of a bath bomb to happen?
What We Did: After revisiting the four beakers still set up in the lab containing last week’s 4-recipe homemade bath bomb investigation, student added some ’72+ hour’ observations to their science notebooks. In C period, students then chose one of the bath bomb ingredients of interest to them and began thinking about how to design and perform a fair test with that particular ingredient. In D period, students discussed some of the bath bomb ingredients of interest to them, but unfortunately ran out of time to begin thinking about how to design and perform a fair test with them.
What We Figured Out: Students in both classes seem pretty confident that gas bubbles are created by combining baking soda and citric acid with water. We have little evidence, however, as to whether some of the other homemade bath bomb ingredients cause gas bubbles OR simply enhance (or suppress?) their formation.
How We Represented It: —
Homework: —
Lesson 2 - Tuesday, Oct 17
Focus Question: What causes the bubbling of a bath bomb to happen?
What We Did: C & D period followed different pathways today. In C period, students created new homemade bath bombs by using Recipe C, the best bubbling bath bomb when tested, but yet manipulating the presence/absence of one ingredient in the original recipe: Paul (table salt vs. epsom salt vs. no salt); Kevin (sugar vs. no sugar); Matteo (water vs. no water); Mimi (olive oil vs. coconut oil vs. no oil); Maria (cornstarch vs. no cornstarch); Leo (sugar-free lemonade mix vs. original lemonade mix vs. no lemonade mix). In D period, students performed an investigation in which two pre-measured bath bomb ingredients–baking soda (7 g) and citric acid (7 g)–were combined with water (14 g) in a small glass beaker. When combining these three ingredients on an electronic balance, we saw the mass of the mixture decrease during the 20 or so minutes we performed the investigation. To document this investigation, we created a new entry in our science notbook and called it, “INV#7.1.2 – Acid + Soda = Mass?” You can see an example of our recorded work in the Grade 7 Notes Portal.
What We Figured Out: In D period, we figured out that bubbles consist of gases, gases contain atoms, atoms have mass, and therefore a bubbling mixture of baking soda, citric acid, and water is losing mass–or atoms–in the form of escaping gas!
How We Represented It: You can see an example of D period’s recorded work in the Grade 7 Notes Portal.
Homework: There is no science homework tonight.
Lesson 3 - Wednesday, Oct 18
Focus Question: What causes the bubbling of a bath bomb to happen?
What We Did: C & D period followed different pathways today. In C period, tested four of their newly created new homemade bath bombs by using Recipe C, the best bubbling bath bomb when tested, but yet manipulating the presence/absence of one ingredient in the original recipe Today’s test teams included Matteo (water vs. no water), Mimi (olive oil vs. coconut oil), Maria (cornstarch vs. no cornstarch), and Leo (sugar-free lemonade mix vs. no lemonade mix). On Friday, the entire class will team up to help Paul (table salt vs. epsom salt vs. no salt), Kevin (sugar vs. no sugar), Mimi (no oil), and Leo (original lemonade mix) create their bath bombs for next week’s tests. In D period, students learned how to do separation procedure using evaporation dishes and bunsen burners. Make use of some left-over bath bomb water, students attempted to evaporate the water from the solution and capture any solid substances remaining in the evaporation dishes. At the conclusion of the procedure, students put a sample of the remaining substance(s) in water to see if it would produce any bubbling activity, which it didn’t! Students then began stirring the new mixture to see if the solid mystery substance(s) would dissolve, which it did, completely!
What We Figured Out: D period figured out that the solid substance(s) remaining in the evaporation dishes could not be baking soda and citric acid. D period also figured out that dissolving is an action in which the original substance remains, but only in smaller and smaller ‘pieces.’ In other words, dissolving the mystery substance(s) in water did not create anything new when we stirred it.
How We Represented It: C period students recorded videos of their bath bomb investigations with their iPads and recorded their observations (and measurements) in their science notebooks. They will be asked to represent what they learned in future lessons. D period, did not represent what they figured out, and so, they need to find a way of representing what they learned in some form during their next lesson.
Homework: There is no science homework tonight, but it would be good for students to work on some of their graded concepts and skills on their own before Friday’s science lesson.
Lesson 4 - Friday, Oct 20
Focus Question: What causes the bubbling of a bath bomb to happen?
What We Did: In C period, students created more homemade bath bombs by using Recipe C, the best bubbling bath bomb when tested, but yet manipulating the presence/absence of one ingredient in the original recipe: Paul & Matteo (epsom salt, no salt); Kevin (no sugar); Mimi (no oil); Leo (original lemonade mix); Maria (original recipe for comparison). In D period, students were treated to their first student presentation, a presentation by Ishaan who volunteered to share his thinking–and research–with his classmates about the molecular nature of both the starting/before and final/after products of the bath bomb chemical reaction. Ishaan’s presentation is now in a newly created section of the Google Science Classroom called “Student Presentations.”
What We Figured Out: C period students will figure out much more on Monday when they test their different homemade bath bombs, which need to cure over the weekend, and compare them to their already-tested bath bombs. Thanks to Ishaan’s presentation, D period students now have an idea of what molecules such as water, carbon dioxide, citric acid, baking soda, and sodium citrate look like (in terms of their atoms). They also came up with a working definition of a “chemical reaction” and recorded a “law of conservation of mass/atoms.”
How We Represented It: C period will be asked to represent what they learned in future lessons following the testing (comparison) of their various homemade bath bomb recipes. Ishaan gave D period two important representations today: a model of the key molecules we think are involved in the bath bomb reaction AND a mathematical formula to describe the reaction.
Homework: There is no science homework due on Monday, but it would be good for students to work on some of their science ideas and science skills outside of school.
Announcements...
The DRIVING QUESTION of our current unit is: How can we make something new that was not there before?
#1 - Students have been asked to demonstrate the following Science Ideas (SIs) before the midterm reports on 13 November: States of matter (solid, liquid, gas).
#2 - Students have been asked to demonstrate the following Science Skills (SSs) before the midterm reports on 13 November: Identifying variables (independent, dependent, controlling/constants) and Writing research questions.