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Sample Learning Goals
Define “isotope” using mass number, atomic number, number of protons, neutrons and electrons.
Given information about an element, find the mass and name of an isotope.
Give evidence to support or dispute: “In nature, the chance of finding one isotope of an element is the same for all isotopes.”
Find the average atomic mass of an element given the abundance and mass of its isotopes.
Predict how the mass and name of an isotope will change given a change in the number of protons, neutrons or electrons.
Predict how the average atomic mass of an element changes given a change in the abundance of its isotopes.

In this lesson, students will define the terms theory and model as well as describing the development of the modern atomic theory as a result of the contributions of Democritus, Thomson, Dalton, and Rutherford.

In this lesson, students will define the terms isotopes, atomic number, mass number and atomic mass as well as being able to determine the number of subatomic particles in the isotope of an element.

In the first lesson of this project, students identified tillage systems and their effects on soil. This second lesson in the sequence identifies the role of cation exchange in soil fertility and examine the relationship between soil structure and cation exchange capacity.