Learning Resource Type

Lesson Plan

Is Gatorade the Only Source of Electrolytes?

Subject Area

Science

Grade(s)

9, 10, 11, 12

Overview

Students will consider the marketing campaigns of Gatorade to help identify what makes a substance an electrolyte.  Students will plan and conduct an investigation to test common ionic and covalent substances to determine if the substance is an electrolyte or non-electrolyte when dissolved in solution.  

This lesson results from a collaboration between the Alabama State Department of Education and ASTA.

    Science (2015) Grade(s): 09-12 - Chemistry

    SC15.CHM.6

    Use mathematics and computational thinking to express the concentrations of solutions quantitatively using molarity.

    Unpacked Content

    UP:SC15.CHM.6

    Vocabulary

    • Molarity
    • Moles
    • Volume
    • Solution
    • Solute
    • Solvent
    • Concentrations
    • Dissolving
    • Solubility
    • Ionic
    • Covalent
    • atomic/ molecular/ particulate level
    • macroscopic level
    • pH
    • hydronium ion
    • hydroxide ion
    • concentration
    • concentrated
    • dilute
    • acids and bases (strong/ weak)
    • properties

    Knowledge

    Students know:
    • The mole is used to convert between the atomic/ molecular and macroscopic levels.
    • Concentrations of solutions can be compared quantitatively using molarity.
    • Mathematical representations may include calculations, graphs or other pictorial depictions of quantitative information.
    • Solutions are a type of mixture that appears homogeneous at the macroscopic level but may be heterogeneous at the atomic/ molecular level.
    • Solutes are the portion of a solution present in the lesser amount.
    • Solvents are the portion of a solution present in the greater amount.
    • Both temperature and pressure affect the solubility of solutes.
    • The effect of temperature on the solubility of a liquid or solid solute differs from that of gaseous solutes.
    • The effect of pressure on the solubility of gaseous solutes differs from that of liquid or solid solutes.
    • The ability of a substance to conduct electricity is determined by the presence of charged particles that are able to move about freely.
    • Ionic compounds typically conduct electricity when melted or dissolved in water because the charged particles are able to move about freely.
    • Covalent compounds typically do not conduct electricty when melted or dissolved in water because there are no charged particles.
    • Exceptions to the typical conductivity of solutions include strong acids, which ionize in water solutions.
    • An acid has more hydronium ions than hydroxide ions.
    • A base has more hydroxide ions than hydronium ions. pH is a measure of the number of hydronium ions present in a solution.

    Skills

    Students are able to:
    • Identify solute and solvent in a solution.
    • Calculate the molarity of a solution.
    • Represent the process of dissolving using a model.
    • Analyze data using tools, technologies, and/ or models to identify relationships within the datasets.
    • Use analyzed data as evidence to describe the relationships between temperature changes and pressure changes on solubility.
    • Plan an investigation that outlines the experimental procedure, including safety considerations, how data will be collected, number of trials, experimental setup, and equipment required.
    • Conduct a planned investigation to test the conductivity of common ionic and covalent substances in solution.
    • Analyze collected and recorded data from investigation to determine conductivity of common ionic and covalent substances.
    • Use the pH scale to determine if a substance is acidic or basic.
    • Determine the concentration of hyfronium or hydroxide ions in a solution based on pH value.

    Understanding

    Students understand that:
    • Mathematical representations of phenomena are used to describe explanations.
    • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
    • Proportional relationships among different types of quantities provide information about the magnitude of properties.
    • Models are used to predict the relationships between systems or components of a system.
    • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
    • Proportional relationships among different types of quantities provide information about the magnitude of properties.
    • Data can be analyzed using tools, technologies, and/ or models (e.g., computational, mathematical) in order to make valid and reliable scientific claims.
    • Different patterns may be observed at each of the scales at which a system is studied and ca provide evidence for causality in explanations of phenomena.
    • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
    • Empirical evidence is required to differentiate between cause and correlation and make claims about specific causes and effects.
    • Scientists plan and conduct an investigation individually and collaboratively to produce data to serve as the basis for evidence, and in the design decide on types, how much, and accuracy of data needed to produce reliable measurements.
    • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
    • The function of a material and its macroscopic properties are related to the atomic/ molecular level structure of the material.
    • Models are used to predict the relationships between systems or components of a system.
    • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
    • Proportional relationships among different types of quantities provide information about the magnitude of properties.

    Scientific and Engineering Practices

    Developing and Using Models; Planning and Carrying out Investigations; Analyzing and Interpreting Data; Using Mathematics and Computational Thinking

    Crosscutting Concepts

    Patterns; Cause and Effect; Scale, Proportion, and Quantity; Structure and Function
    Science (2015) Grade(s): 09-12 - Chemistry

    SC15.CHM.6a

    Develop and use models to explain how solutes are dissolved in solvents.

    Science (2015) Grade(s): 09-12 - Chemistry

    SC15.CHM.6c

    Design and conduct experiments to test the conductivity of common ionic and covalent substances in a solution.

    Primary Learning Objectives

    Learning Targets:

    • I can identify a substance as being an electrolyte or a nonelectrolyte. 
    • I can design and conduct an experiment to test the conductivity of common ionic and covalent substances in a solution. 

    Procedures/Activities

    Before:

    Start a class discussion by asking students if they have heard of electrolytes before and then continue the conversation by asking them where.  Many students are familiar with electrolytes from advertisements for Gatorade. Discuss how electrolytes are important for many processes in the human body, and ask students if they know of other sources for obtaining electrolytes.  You may wish to tell students what an electrolyte is or have them look up the definition.  

    During:

    1. Students will work collaboratively to complete "What Makes a Substance an Electrolyte?" activity by designing their own investigation with a set of given materials to test the conductivity of common ionic and covalent substances in a solution.  After the teacher approves the investigation, students will conduct their experiment.  By working collaboratively students will develop teamwork, communication, and problem-solving skills. 
    2. Students will work collaboratively to complete the card sort activity to classify common ionic and covalent substances in a solution as electrolytes or nonelectrolytes based on conductivity.  The card sort activity is attached.  Print one set per group and cut the cards apart.  Students will use the knowledge gained from "What makes a substance an electrolyte" activity to sort the compounds listed into 2 groups: electrolytes and nonelectrolytes.

    After:

    Watch Video: What happens when stuff dissolves? and discuss as a class why ionic compounds are good conductors (electrolytes) and why covalent compounds are nonelectrolytes.  Relate to the introduction discussion and have students list other sources of electrolytes.  Discuss why Gatorade may emphasize electrolytes in advertising campaigns.

    Assessment Strategies

    • The students will be assessed on their ability to design and conduct an experiment to test the conductivity of common ionic and covalent substances in a solution during the activity "What makes a substance an electrolyte?"
    • The students will be assessed for understanding of conductivity of common ionic and covalent substances in a solution during the card sort activity.
    • The students will be informally assessed during class discussion to identify preconceptions and especially any misconceptions.
    • Sample test question:  Have students draw a diagram that shows what happens on the atomic level when sugar dissolves in water and when salt dissolves in water and use the picture to explain why ionic compounds are electrolytes.  

    Acceleration

    For an extension activity, students can research how a lack of electrolytes or an excess of electrolytes affects the human body. 

    Approximate Duration

    Total Duration

    61 to 90 Minutes

    Background and Preparation

    Background/Preparation

    Students should have a strong understanding of ionic and covalent bonding.

    Materials and Resources

    Materials and Resources

    Water

    Electrical conductivity testers (1 per group is ideal)

    Sugar

    Salt

    Epson Salt

    Moth Balls

    Mortar and pestle (1 per group is ideal)

    Beakers (250 mL- about 4 per group)

    Stirring rods (about 4 per group)

    Electrolyte Nonelectrolyte Card Sort activity- print and cut 1 set of cards for each group.  Make certain to shuffle the cards.  If you print on cardstock and laminate the cards can be reused multiple times.

    "What Makes a Substance an Electrolyte" activity

    Technology Resources Needed

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