6th Grade Earth Science Curriculum Unit 1: Introduction to Scientific Methods Lesson 19: Convection in the Air Objectives: After completing the lesson, students will be able to: describe the process of convection as it occurs in air Key Question: "What happens when heat is applied unevenly to air?" Overview: In this lesson, the teacher presents three demonstrations designed to illustrate how convection takes place in air. In the first demonstration, carbon dioxide extinguishes a flame, after flowing down a ramp. In the second demonstration, students notice the diffusion of heated scented oil through the air. In the third demonstration, the "shadow" of convection currents is observed on a projection screen. Finally, in the fourth demonstration, students witness the movement of incense in an aquarium that has near boiling water at one end, and ice at the other. In this final demonstration, students also witness a modeling of the formation of clouds, due to condensation. Students then get an opportunity to answer questions about real world phenomena using their understanding of convection. Time Required: 40-60 minutes (1 class session). Materials: for the class 1 bottle of flavored extract (strawberry, coconut, or lemon work well) shallow, heat resistant container hot plate padded tongs, or hot pad candle and matches vinegar baking soda 500 ml beaker, or peanut butter jar strip of heavy card stock, about 12" x 3" white projection screen or a 24" x24" piece of white poster board or paper overhead projector incense ice boiling water styrofoam cup 10 gallon aquarium for each student a copy of "Convection Worksheet A" and "Convection Worksheet B" (pp. 24-25 of the Convection: a Current Event GEMS guide) Procedure: for the first three demonstrations and the follow-up discussion, see pp. 19-22 in the Convection: a Current Event GEMS guide. For the final demonstration, place ice on the bottom of one end of a 10 gallon aquarium. At the other end of aquarium, place a stick of lit incense and a cup of boiling water. Then, cover the aquarium with a sheet of heavy paper, glass, Plexiglas, or wood. Assessment: completed "Convection Worksheet A" and "Convection Worksheet B" Homework: completed "Convection Worksheet A" and "Convection Worksheet B" OUSD Science Content Standards (State of California Science Content Standards): #1-b, e, f; #3-c, d; and, #4-c (#1-c; #3-c, d; and, #7-b, d, e) References: Gould, Alan. Convection: a Current Event. Berkeley, CA.: Lawrence Hall of Science, University of California, Berkeley, 1988, pp. 17-26. Notes: This lesson should remind students of the demonstration from Lesson 8: "Floating Bubbles." It is also possible to combine this lesson with Lesson 8. For the final demonstration, it may be necessary to turn out the lights, and/or shine a strong light from behind the aquarium for the students to see this effect completely. By the time the lesson ends, students should understand that the property of density and the concept of "floating" provides an explanation of the process by which convection occurs. The Convection: a Current Event GEMS guide section titled "Going Further" provides information and diagrams that work well in many of the other units that are taught later in the school year. Unit 1 Introduction amnd Overview Unit 1 Vocabulary Lesson 1: Laboratory Safety and Classroom Management Lesson 2: Observation and Inference Lesson 3: Introduction to Observation Lesson 4: Comparing H2O to CO2 Lesson 5: Matter and Energy Lesson 6: Exploring Dry Ice Lesson 7: Marge's Systematic Observation Lesson 8: Floating Bubbles Lesson 9: Marge's Experiment Lesson 10: Investigable Questions Lesson 11: Planning an Investigation Lesson 12: Conducting Investigations Lesson 13: Sharing Results Lesson 14: Layering Liquids Lesson 15: Layering Salt Solutions Lesson 16: Density in Everyday Life Lesson 17: Observing Convection Lesson 18: Understanding Convection Lesson 19: Convection in Air Lesson 20: Intro to Measurement Lesson 21: How Big is my Favorite Stuffed Animal? Lesson 22: Measuring Volume Lesson 23: Gummy Bear Lab Back to Grade 6 Units