Elements and Compounds
- Distinguish between an element and a compound.
- Identify the four elements that make up 96% of living matter.
- Define the term trace element and give an example.
Atoms and Molecules
- Draw and label a simplified model of an atom. Explain how this model simplifies our understanding of atomic structure.
- Distinguish between each of the following pairs of terms:
- neutron and proton
- atomic number and mass number
- atomic weight and mass number
- Explain how the atomic number and mass number of an atom can be used to determine the number of neutrons.
- Explain how two isotopes of an element are similar. Explain how they are different.
- Describe two biological applications that use radioactive isotopes.
- Define the terms energy and potential energy. Explain why electrons in the first electron shell have less potential energy than electrons in higher electron shells.
- Distinguish among nonpolar covalent, polar covalent and ionic bonds.
- Explain why strong covalent bonds and weak bonds are both essential in living organisms.
- Distinguish between hydrogen bonds and van der Waals interactions.
- Give an example that illustrates how a molecule’s shape can determine its biological function.
- Explain what is meant by a chemical equilibrium.