Identifying and Naming Isotopes: ''EggCeptional'' Isotopes (page 2)

The nucleus (central core) of an atom consists of protons (positively charged particles) and neutrons (particles that don't have any electrical charge). Electrons (negatively charged particles) are found in levels, or orbitals, outside the nucleus. An electrically neutral atom has an equal number of protons and electrons. Some atoms occur as isotopes—two or more atoms with the same atomic number but different numbers of neutrons. When writing the name of an isotope, you write the name of the element, a hyphen, and the sum of the number of protons and neutrons found in the nucleus of that atom. For example, bromine-80 is an isotope with 35 protons, 35 electrons, and 45 neutrons.

Materials

Plastic egg isotope (prepared by the teacher; see Teacher's Notes); Periodic table

Activity

1. Obtain an egg isotope from your teacher. This represents one of the isotopes of an element on the periodic table.
2. Examine the egg carefully and identify which structures inside the egg represent protons, neutrons, and electrons. The egg itself is the nucleus of the atom.
3. Use the periodic table to identify the element your egg represents.
4. Determine the specific isotope of the element.

Follow-Up Questions

1. Which part of the egg represented each of the following? How many of each did you find?
   1. Protons
   2. Neutrons
   3. Electrons
2. Which element did your egg represent?
3. Write the correct isotope name.

Answers

1. Answers will vary.
2. Answers will vary.
3. Answers will vary.

Extension

Obtain the eggs of five of your classmates. Write down the names of the isotopes of those five eggs. Compare your answer with your classmates' answers. Did you agree or disagree with their determinations?