8th Grade Chemical Leavening Lab
Objective: Students will examine the effect various liquids have on chemical leavening agents and chart the reactions.
Materials: Leaving agent handout, baking soda, baking powder, milk, water, vinegar, buttermilk, cups, teaspoons, baking pans, supplies for washing up,
Time: 45 minutes
Introduction: (5 minutes)
Question: Which core school subject is baking the most similar to? Answer – chemistry
Review the seven essential ingredients in baking.
Key Ideas: (5 minutes)
Leavening Agents
*Review the different forms of leavening agents (trapped air, steam, chemical, and yeast)
*Questions: What are the two kinds of chemical leaving agents?
Can you substitute one chemical leavening for the other? Why or Why not?
Activity: (30 minutes)
Students will work in groups of four. Each group will be given the same equipment, four labeled liquids and two unmarked white powders. Groups will generate a hypothesis statement before beginning the experiment. As the different powders are combined with the liquids, students should record their observations of the differing reactions. When all combinations have been tried, students should identify each of the white powders based on the reactions. After the students have identified the powders, they should clean up their supplies and answer the questions at the bottom of the lab page.
REMIND STUDENTS: They will not receive any additional supplies; they should ensure there is enough of each powder and each liquid to accomplish all reactions.
Check for Understanding: (5 minutes)
*Come together as a class and identify powder A and powder B. What lead you to make the decisions? Which liquids reacted best? Why?
Assessment
*Assessment: informal observations during group work time, formal assessment of the completion of the chart and response to questions.
Materials: Leaving agent handout, baking soda, baking powder, milk, water, vinegar, buttermilk, cups, teaspoons, baking pans, supplies for washing up,
Time: 45 minutes
Introduction: (5 minutes)
Question: Which core school subject is baking the most similar to? Answer – chemistry
Review the seven essential ingredients in baking.
Key Ideas: (5 minutes)
Leavening Agents
*Review the different forms of leavening agents (trapped air, steam, chemical, and yeast)
*Questions: What are the two kinds of chemical leaving agents?
Can you substitute one chemical leavening for the other? Why or Why not?
Activity: (30 minutes)
Students will work in groups of four. Each group will be given the same equipment, four labeled liquids and two unmarked white powders. Groups will generate a hypothesis statement before beginning the experiment. As the different powders are combined with the liquids, students should record their observations of the differing reactions. When all combinations have been tried, students should identify each of the white powders based on the reactions. After the students have identified the powders, they should clean up their supplies and answer the questions at the bottom of the lab page.
REMIND STUDENTS: They will not receive any additional supplies; they should ensure there is enough of each powder and each liquid to accomplish all reactions.
Check for Understanding: (5 minutes)
*Come together as a class and identify powder A and powder B. What lead you to make the decisions? Which liquids reacted best? Why?
Assessment
*Assessment: informal observations during group work time, formal assessment of the completion of the chart and response to questions.
lesson reflection
Curiosity is a wonderful thing. Some of the greatest discoveries began with the question of why? Why do baked goods rise? How does it work? Why is it important for quick breads to be made quickly? Adolescents are in a time of discovery, not only of themselves, but of the world around them. Children begin asking why at a very young age, and the desire to know never really goes away. We simply begin to seek for a deeper understanding of concepts. As sixth graders, my students are introduced to baking, balance of ingredients, and recipe order. It is not until eighth grade that we explore in depth the specific functions of ingredients within a recipe.
I believe in hands-on learning. Both Howard Gardner and Jerome Bruner illustrate the importance of hands-on, active, discovery based learning. Middle school students do not like to sit still. When learning becomes active, student are engaged and motivated to continue the process. By having working in a science lab-like setting, students are accomplishing the discovery aspect of their learning. I could tell them why baking soda reacts with vinegar and not water, but if they explore the concept first hand, they will learn more. As the students conduct the experiment, they can see firsthand how baking powder and baking soda differ, and what kinds of ingredients are needed to cause the reaction. We carry this information over into our lessons on quick breads and recipe alterations. If a recipe contains baking soda, there must be some kind of acid to cause the reaction, so can you replace the buttermilk with water?
By drawing on an adolescent’s natural curiosity, I can teach concepts in an engaging way. The students have the opportunity to socialize while still exploring concepts and their potential future application.
I believe in hands-on learning. Both Howard Gardner and Jerome Bruner illustrate the importance of hands-on, active, discovery based learning. Middle school students do not like to sit still. When learning becomes active, student are engaged and motivated to continue the process. By having working in a science lab-like setting, students are accomplishing the discovery aspect of their learning. I could tell them why baking soda reacts with vinegar and not water, but if they explore the concept first hand, they will learn more. As the students conduct the experiment, they can see firsthand how baking powder and baking soda differ, and what kinds of ingredients are needed to cause the reaction. We carry this information over into our lessons on quick breads and recipe alterations. If a recipe contains baking soda, there must be some kind of acid to cause the reaction, so can you replace the buttermilk with water?
By drawing on an adolescent’s natural curiosity, I can teach concepts in an engaging way. The students have the opportunity to socialize while still exploring concepts and their potential future application.