Summary

In this activity, students are introduced to the periodic table and its elements. Student will discuss that all material in the Universe is composed of elements and that the atom is the smallest particle that still has the physical and chemical properties of any given element. Students will engage in an activity to determine the percent composition of common elements in the universe, and based on their results they will hypothesize the identity of each element based on its relative abundance.

Grade Level

Middle School

Objectives

By the end of this activity, students should be able to

• Identify the chemical compositions of the universe.
• Recognize common elements on the Periodic Table.

Chemistry Topics

This activity supports students’ understanding of

• Periodic Table
• Elements
• Atoms
• Percent Composition

Time

Teacher Preparation: 30-45 minutes

Lesson: 60 minutes

Materials

• Plastic beads in 10 different colors (available at craft stores, or you can purchase a package 1000 beads on Amazon) Quantity of beads will depend on class size and student grouping
• Lap sized dry erase/white board, 1 per group
• Expo markers, 1 per group
• 3-4 Plastic cups per group

Safety

• There are no safety considerations for this activity.
• If you are doing this with elementary aged students, you might remind them of the choking hazard.

Teacher Notes

• Before beginning the lesson, have all beads pre-mixed in different buckets (one for each planet)
• I always group students by handing them cards as they walk in (either numbered or pictures). They then have to find the other students with that picture or number to find their group. This can be a little hectic the first few times. This works best with groups of 3-4.
• I normally scoop beads with a large cup and give students 3-4 small cups to use for sorting beads.
• For classroom management purposes, I do not have materials out at student desks when they walk in. One student from each group is the materials manager and has to come get their beads from me once instructions are given. You can easily assign this as the youngest, oldest, nearest birthday, etc. in the group of students.
• To create the mix of beads for the universe, I usually use a 1 cup measuring cup or something equivalent and mix the following:
  • 50 scoops of clear beads (to represent 90% abundance of hydrogen in Universe)
  • 5 scoops of light blue beads (to represent 9% abundance of helium)
  • 3 scoops of dark blue beads (to represent 0.08% abundance of oxygen)
  • 2 scoops of black beads (to represent 0.03% abundance of carbon)
  • 1 scoop of green beads (to represent 0.01% abundance of nitrogen)
  • 1 scoop of orange beads (to represent 0.01% abundance of neon)
  • 1 scoop of pink, purple, red, and yellow beads in roughly equal amounts (to represent 0.01% abundance of magnesium, silicon, iron, and sulfur together)
• I have students use the small dry erase boards to show all of their work when determining the percentages of each bead color present in their sample.
• The lightest elements (hydrogen and helium) were created in the Big Bang. These elements combined to form stars. Stars are big balls of hot gas, mostly hydrogen. Stars generate energy by converting hydrogen to a heavier element, helium, through the process of nuclear fusion (two or more lighter atoms are combined to create a heavier atom).
• All elements are made of atoms. Each atom is composed of a nucleus (protons and neutrons) and an electron cloud (electrons). The number of protons in the nucleus of an atom determines that element’s identity. The number of electrons and neutrons can change (ions and isotopes), but the number of protons is constant.
• As an extension to this activity, you could have students compare the chemical compositions of the universe to the composition of the Earth and of the human body.