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Integrating Chemistry & Algebra II

Isotopic Pennies

Introduction:

Using the idea of the atomic mass of an element is a weighted average, this activity uses a system of equations to determine the number of each type of “atom” in a close container.

Learning Outcomes:

  • Students will be able to set up a system of equations to determine the number of “atoms” in a closed container.
  • Students will be able to connect this activity to the way scientists are able to determine the relative abundance of isotopes in a sample.
  • Students will be able to set up and solve a system of equations from data they collect.

Curriculum Alignment:

Chemistry SCOS:

  • 1.01 Design, conduct and analyze investigations to answer questions related to chemistry.
  • 2.02 Examine the nature of atomic structure.

Algebra 2 SCOS:

  • 2.10 Use systems of two or more equations or inequalities to model and solve problems; justify results. Solve using tables, graphs, matrix operations, and algebraic properties.

Classroom time required:

  • 45 minutes

Materials needed:

  • 1 empty balloon
  • 10 pre-1982 pennies
  • 10 post-1982 pennies
  • 1 balloon with 10 pennies
  • Some pre and some post
  • Balance.

Pre-activities:

  • The students need to be able to define an isotope and calculate the atomic mass when given the masses of isotopes and their respective percent abundances.
  • The students need to be familiar with setting up and solving a system of equations.

Activities:

Students will collect mass data of an empty balloon, pre and post 1982 pennies, and their assigned balloon. They will then use that information to set up their system in order to determine the number of pre and post 1982 pennies they have in their balloon.

Assessment:

  • Post Lab Questions

Critical vocabulary:

  • Isotope
  • System of equations
  • Percent abundance

Comments:

This activity worked best when the Algebra 2 teacher had students do it after they had completed a simple calculate the atomic mass of an element simulation in chemistry class. However, this activity can be done in either an Algebra 2 or a Chemistry class as a standalone activity. It will be helpful to students either way.

Supplemental Files: