Learning Resource Type

Learning Activity

What Just Happened?

Subject Area

Science

Grade(s)

8

Overview

This learning activity should be used during a lesson on chemical and physical reactions. The students will observe and analyze the characteristic properties of vinegar and baking soda.  They will also conduct an experiment and determine if a chemical reaction has occurred.

This activity was created as a result of the ALEX Resource Development Summit.

    Science (2015) Grade(s): 8

    SC15.8.5

    Observe and analyze characteristic properties of substances (e.g., odor, density, solubility, flammability, melting point, boiling point) before and after the substances combine to determine if a chemical reaction has occurred.

    Unpacked Content

    UP:SC15.8.5

    Vocabulary

    • Characteristic properties (e.g., odor, density, solubility, flammability, melting point, boiling point)
    • Substances
    • Chemical reaction

    Knowledge

    Students know:
    • Each pure substance has characteristic physical and chemical properties that can be used to identify it.
    • Characteristic properties of substances may include odor, density, solubility, flammability, melting point, and boiling point.
    • Chemical reactions change characteristic properties of substances.
    • Substances react chemically in characteristic ways.
    • In a chemical process, the atoms that make up the original substances are regrouped into different molecules, and these new substances have different properties from those of the reactants.

    Skills

    Students are able to:
    • Observe characteristic physical and chemical properties of pure substances before and after they interact.
    • Analyze characteristic physical and chemical properties of pure substances before and after they interact.
    • Analyze the properties to identify patterns (i.e., similarities and differences), including the changes in physical and chemical properties of each substance before and after the interaction.
    • Use the analysis to determine whether a chemical reaction has occurred.

    Understanding

    Students understand that:
    • Observations and analyses can be used to determine whether a chemical reaction has occurred.
    • The change in properties of substances is related to the rearrangement of atoms in the reactants and products in a chemical reaction (e.g., when a reaction has occurred, atoms from the substances present before the interaction must have been rearranged into new configurations, resulting in the properties of new substances).

    Scientific and Engineering Practices

    Analyzing and Interpreting Data

    Crosscutting Concepts

    Patterns

    Phase

    During/Explore/Explain
    Learning Objectives

    Learning Objectives

    The students will be able to observe and analyze the characteristic properties of substances before and after the substances combine to determine if a chemical reaction has occurred.

    Activity Details

     

    1. Pass out the What Just Happened T-Chart.
    2. Ask the students to think of words to describe physical reaction and record those words under Physical Reaction on their T-Chart.
    3. Ask the students to think of words to describe chemical reaction and record those words under Chemical Reaction on your T-Chart.
    4. Ask the students to explain the difference between physical reaction and chemical reaction on the bottom of their What Just Happened T-Chart. (Revisit the difference after the lesson.)
    5. Introduce the Learning Activity by asking students what they think will happen when baking soda is mixed with vinegar. (This should be done as a whole group discussion.)
    6. Ask the students to observe and analyze the characteristic properties of the baking soda and write the properties on their What Just Happened T-Chart.
    7. Instruct the students to place two teaspoons of baking soda in the balloon using the funnel.
    8. Next, have students pour vinegar into their bottles so that they are half full (approximately 10 oz).
    9. Then, have the students in each group place the balloon with baking soda in it over the opening of the bottle, but do not allow the baking soda to mix with the vinegar. 
    10. Make sure the students hold the top of the balloon so that it doesn't come off. (The chemical will produce gas and make the balloon pop off, so remind the students of lab safety rules.)
    11. Once the students have observed the reaction, have the students answer the following questions on the bottom of their What Just Happened T-Chart:
    • What type of reaction occurred?
    • What happened to the baking soda once it was combined with the baking soda?
    • What is formed inside the balloon?
    Assessment Strategies

    Assessment Strategies

    The teacher should assess student comprehension through teacher questioning and class discussions. 

    The teacher should assess the What Just Happened T-Chart for correctness as well.

    Variation Tips

    To help reduce time, the teacher could:

    • Pour 10 oz of vinegar in a 20 oz bottle.
    • Measure out 2 teaspoons of baking soda.

    Background and Preparation

    Background / Preparation

    The teacher will need to group the students in groups of 2-4.

    The teacher will need to print the What Just Happened T-Chart.

    The teacher will need to make sure each group has the following materials to complete the Learning Activity (The materials listed below are for one group and will need to be adjusted for multiple groups)

    1. Vinegar
    2. Round Balloon
    3. Plastic Bottle
    4. Baking Soda
    5. Funnel
    6. Teaspoon

    Digital Tools / Resources

    ALSDE LOGO