BIO 201 Chapter 2 Study Guide Dr Sonja Pyott The chemical basis of life I Atoms molecules and water Note You do NOT need to know about moles Avogadro s number or isotopes page 26 free radicals page 32 and concentration or molarity page 35 Terms to know Matter Atoms Molecules Elements Protons Neutrons Eletcrons Atomic nucleus Rutherford s gold foil experiment Orbitals Energy shells Valence electrons Atomic number Periodic table Atomic mass Dalton Trace elements Molecular formula Compound Covalent bond Octet rule Electronegativity Polar covalent bonds Nonpolar covalent bonds Polar molecules Nonpolar molecules Hydrogen bond Ions Anions Ionic bonds Chemical reaction Reactants Products Solutes Solvent Aqueous solutions Hydrophilic Hydrophobic Colligative properties of water Specific heat Cohesion Adhesion Surface tension Hydrogen ion Hydroxide ion Acid Base pH scale Buffer Important figures 2 1 2 2 2 3 2 4 2 5 2 7 2 8 2 9 2 10 2 11 2 12 2 13 2 16 2 18 2 20 2 21 Important tables 2 1 2 2 2 3 Learning goals At the conclusion of this module you should be able to Define atom element compound and molecule State the four most common elements in living matter Describe the subatomic arrangement of protons neutrons and electrons in an atom Distinguish atomic number atomic mass and valence Describe Rutherford s gold foil experiment and how the results contributed to our modern understanding of subatomic structure Classify chemical bonds as either covalent ionic or hydrogen and rank them according to their relative strength Distinguish polar from nonpolar covalent bonds Page 1 of 2 BIO 201 Chapter 2 Study Guide Dr Sonja Pyott Describe how differences in electronegativity of atoms result in polar covalent bonds between those atoms Explain how valence electrons determine the types of chemical bonds formed Predict the type of chemical bond an atom will be likely to make based on the number of its valence electrons Define chemical reactions reactants and products Describe the structure and geometry of a water molecule Explain the relationship between the polar nature of water and its ability to form hydrogen bonds Summarize four characteristics of water that result from hydrogen bonding and are essential to life Describe and interpret the pH scale Explain how acids and bases affect the hydrogen ion concentration of a solution Provide an example of an acid and a base Define buffers and explain their importance to living organisms Page 2 of 2