CH 2 & 3 STUDY GUIDE : BASIC CHEMISTRY
KEY TERMS
matter
dissociation
anion
inorganic
ionic bond
cation
atom
valence
hydrogen bond
element
ionization
hydrophobic
atomic nucleus
molecule
hydrophobic
interactions
proton
molecular formula
hydration
neutron
structural formula
hydrophilic
atomic number
compound
bound water
mass number(=atomic
weight)
acid
surface tension
base
isotope
hydrogen ion
capillarity (=capillary
action)
hydroxide ion
specific heat
pH
freezing point of water
buffer
heat of vaporization
nonpolar covalent
bond
solvent
electron
valence electrons
orbital
octet rule
half-life
solute
radioactive tracer
polar covalent bond
aqueous solution
ion
ionic bond
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WORD ROOTS
an - = not (anion: a negatively charged ion)
co - = together; - valent = strength ( covalent bond: an attraction between atoms that share one
or more pairs of outer shell electrons)
electro - = electricity (electronegativity: the tendency for an atom to pull electrons towards itself)
iso - = equal (isotope: an element having the same number of protons and electrons but a
different number of neutrons)
neutr- = neither (neutron: a subatomic particle with a neutral electrical charge)
pro - = before (proton: a subatomic particle with a single positive electric charge)
kilo - = thousand (kilocalorie: a thousand calories)
hydro - = water; - philos = loving; - phobos = fearing (hydrophilic: having an affinity for water;
hydrophilic: having an aversion to water)
QUESTIONS
1. Describe atomic structure, using the terms proton, neutron, electron, mass
number and orbital. Indicate what is meant by electrons in an "excited state" and
those in a "ground state"
2. Explain what an isotope is and give two important physical properties of
isotopes that make them useful in biological research. Define half-life.
3. Using diagrams, explain what an ion is, and how it forms. Describe an ionic
bond.
4. Explain what is meant by pH. Give the name of materials that resist a change
in pH.
5. Describe a covalent bond and tell how it differs from an ionic bond. Relate the
structure of an atom to its chemical properties and to the type of chemical bond it
forms.
6. Explain the important role of weak chemical bonds in the organization of living
things.
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7. Describe the special physical properties of water. Draw two water molecules in
a way that illustrates a hydrogen bond, explain why water is a good solvent and
show the basis for the high surface tension of water.
How do the unique chemical and physical properties of water make life on earth
possible?
8. Indicate why oxygen and carbon dioxide are basic to life, and name the
principle source of each of these molecules.
9. What is the difference between a mixture, compound, and a molecule?
10. What is the difference between a polar and nonpolar covalent bond?
11. What properties of water make it an essential component of living material?
12. What is pH? Explain the pH scale, acids, and bases. Why is pH biologically
important?
13. Why are buffers important to living things? Explain how a buffer system
works.
14. Explain why isotopes are important in biochemical research?
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