The Atomic Model:

Hands on activity exploring the advanced Bohr model for the atom

Author(s)

Michael Starr

Subjects

Chemistry

Grade level

10-11

Duration

One 47-minute class

Rationale (How this relates to engineering and the STEMcinnnati theme)

Throughout history of its development the concept of the atom has been largely theoretical. Only recent techniques have made it possible to actually capture a glimpse of atoms their shapes and inner workings. Even then it still requires substantial amounts of abstract thought to understand the intricate workings of the atom and scientists are still baffled by many of its behaviors. This makes it a very difficult subject to convey to students. However, it is necessary to teach basic concepts because the fundamentals of engineering are based on the understanding and harnessing of the power of atoms and their interactions with each other.

Activity Summary

Students will be participating in a hands-on lesson concerned with the Bohr atomic model. Atomic bingo will consist of instructions for placing color coated candy in the locations on the worksheet provided which contains a blank Bohr model. Once all the pieces have been placed in their respective positions on the worksheet the first student to raise their hand with the correct model and element name will be rewarded with praise and candy.

Activity / Time
Catch and preassessment / 7 mins
Objectives/Starting information / 10 mins
Bingo atoms / 15 mins
Discussions / 5 mins
Objectives/Review / 5 mins
Post assessment / 5 mins

Objectives

Upon completion of this lesson, students will be able to:

  1. Identify protons, neutrons, and electrons as sub-atomic particles
  2. Identify the charge of protons, neutrons and electrons
  3. Locate where protons, neutrons and electrons go on a Bohr atomic model
  4. Indicate number of elections in the different orbital shells (i.e. 1s, 2s, 2p, etc.) of a particular element
  5. Indicate the number of protons and neutrons in the nucleus of a particular element or isotope of an element
  6. Define isotope as having a different number of neutrons

Standards

Ohio Standard: Physical Sciences

9-10 Benchmark A: Describe that matter is made of minute particles called atoms and atoms are comprised of even smaller components. Explain the structure and properties of atoms.

11-12 Benchmark C: Describe how atoms and molecules can gain or lose energy only in discrete amounts.

11-12 Benchmark E: Summarize the historical development of scientific theories and ideas within the study of physical sciences.

Background knowledge

Students will have learned of the sub-atomic particles protons, neutrons and electrons from regular class activities. They will be familiar with the history of the atom and the development of the Bohr atomic model. They have learned what an isotope is and therefore have knowledge about where protons, electrons and neutrons are located in the Bohr model and the numbers of each for a particular isotope of an element.

Materials Required

-Pre-assessment sheet

-Bohr model work sheet

-m&m’s or other color coated candy for protons and neutrons (select two, or one, colors for protons and neutrons)

-Nerds or other smaller candy for elections (additional example – Red Hots)

-Handout on common elemental isotopes and their abundancy

-Post-assessment sheet (same as pre-assessment with additional conceptual questions)

Activities

Gaining Attention: The term Sub-atomic particles will be written on the board as the students take their seats. As class begins a bag of candy for the activity will be pulled out and the students will be asked what the bag contains while emphasizing what is written on the board. For today this candy will be sub-atomic particles.

Stimulating the recall of prerequisite learning: Students will be asked where the protons and neutrons go in the Bohr atomic model and where the electrons go. They will be asked how the number of electrons relates to the number of protons and what the atomic number of an element is. They will be given a handout (attached) listing up to Neon the common isotopes and their relative abundancy to help them in atomic bingo identify the element being described.

Informing learners of the objective: Today you will learn where protons, neutrons and electrons are located on the Bohr atomic model and how to identify isotopes of common elements.

Present the stimulus material (activity): Students will work individually for the atomic bingo exercise and each will be given an isotope handout and Bohr model worksheet as well as a baggie of candy that has been separated into the appropriate colors and numbers. Do this for about 7 or 8 elements and isotopes using carbon or Nitrogen as the largest atom. Will also discuss the isotope tritium as a Spiderman 2 reference can be used (Dr. Octoapus, the villain, is trying to get tritium to make his power generator) and inform students that it is an isotope of hydrogen with 2 neutrons and 1 proton.

Eliciting the desired behavior/review: Students will place their electrons, protons and neutrons in the appropriate locations as the teacher reads off the instructions for constructing a particular element. Reading protons last is a good practice as this is the key to understanding what element it is. Candy reward will be given to the first student to get the correct element.

Assessment of Student Learning

Students will be given a pre-assessment consisting of multiple-choice questions having to do with sub-atomic particles. The same questions will be distributed after the activity along with 3 new questions written on the board.

Assessment of the Activity

Distribution of the STEP activity assessment form to the students and to the teacher.

The Atom! Pre and post assessment questions

  1. The three basic sub-atomic particles are the:
  2. Electron, Einstein and Pluto
  3. Photon, Neutron and Nucleus
  4. Electron, Proton, and Neutron
  5. Nucleus, Electron and Neutron
  1. The electron has a charge.
  2. Neutral
  3. Negative
  4. Positive
  5. Negligible
  1. The Neutron has a charge.
  2. Negative
  3. Positive
  4. Neutral
  5. Negligible
  1. The Proton has a charge.
  2. Positive
  3. Negative
  4. Negligible
  5. Neutral
  1. The nucleus contains the following sub-atomic particles:
  2. Electron and Neutron
  3. Electron and Proton
  4. Proton and Neutron
  1. The number of protons in the nucleus is called the:
  2. Mass Number
  3. Atomic Number
  4. Atomic Weight
  5. Nucleus number
  1. The number of protons and neutrons in the nucleus is called the:
  2. Nucleus number
  3. Atomic number
  4. Mass number
  5. Atomic weight
  1. ______of an element have the same number of protons but a different numbers of neutrons
  2. Allotropes
  3. Isotopes
  4. Ions
  5. None of the above

Elements and their common isotopes:

Hydrogen (Atomic number = 1)

-H1 (Hydrogen) – 1 proton, 0 neutrons. 99.9% abundant

Helium (atomic number = 2)

-He4 (Helium) – 2 protons, 2 neutrons. 99.9% abundant

Lithium (atomic number = 3)

-Li7 – 3 protons, 4 neutrons. 92.5% abundant

-Li6 – 3 protons, 3 neutrons. 8.5% abundant

Beryllium (atomic number = 4)

-Be9 – 4 protons, 5 neutrons. 100% abundant

Boron (atomic number = 5)

-B11 – 5 protons, 6 neutrons. 80% abundant

-B10 – 5 protons, 5 neutrons. 20% abundant

Carbon (atomic number = 6)

-C12 – 6 protons, 6 neutrons. 98.9% abundant

-C13 – 6 protons, 7 neutrons. 1.1% abundant

Nitrogen (atomic number = 7)

-N14 – 7 protons, 7 neutrons. 99.6% abundant

-N15 – 7 protons, 8 neutrons. 0.4% abundant

Oxygen (atomic number = 8)

-O16 – 8 protons, 8 neutrons. 99.8% abundant

Fluorine (atomic number = 9)

-F19 – 9 protons, 10 neutrons. 100% abundant

Neon (atomic number = 10)

-Ne20 – 10 protons, 10 neutrons. 90.5% abundant

-Ne21 – 10 protons, 11 neutrons. 0.3% abundant

-Ne22 – 10 protons, 12 neutrons. 9.2% abundant


Additional questions for post assessment written on the board, have the students write answers on the back of the assessment form.

-Based on today’s activity please rank from least to greatest the relative masses of the proton, electron and neutron. That is, how do their masses compare to one another?

-During today’s activities we discussed the isotope tritium. Deuterium is also an isotope of hydrogen, please list the number of electrons, protons and neutrons present in the isotope deuterium. (emphasize the deu prefix).

-Please list the number of protons, neutrons and electrons present in the isotope carbon 14.