Honors Chapter 6
Assessment answers
Section 1
1. What is the smallest unit of matter?
Atom
2. How are atoms and elements related?
The same type of atoms make up an
element
3. List the similarities and differences
among protons, electrons, and neutrons.
All of these are similar because they make
up an atom.
Protons, neutrons in nucleus
Electrons in outer shell
Protons positive
Electrons negative
Neutrons neutral
4. How does the location of the electrons
in an atom allow them to be involved in
bonding?
Electrons in the outer shell will be nearer
to the outer shells of other atoms and
allow them to bond covalently.
5. Look in the textbook on p. 149 Figure
6.3. What is the most abundant
element that exists in living things?
Hydrogen
6. How does the atom of an isotope differ
from the atom of the same element? How
are they the same?
Differ in the number of neutrons
Similar because they have the same
number of electrons & protons
7. What type of medical test makes use of
radioisotopes? P. 150 in textbook
Radiation therapy, x-rays
8. Why is CO, carbon monoxide not an
element?
It is a compound of carbon and oxygen; 2
different elements
9. Are all compounds molecules?
No
Why or why not?
Only compounds formed by covalent
bonding are molecules
10. Compare van der Waals forces, ionic
bonds, and covalent bonds.
Van der Waals hold molecules together
Ionic and covalent bonds hold atoms
together
Covalent bonds – electrons are shared
between atoms
Ionic bonds – electrical attractions
between two oppositely charged atoms
11. How does the atom of an isotope differ
from the atom of the same element?
Number of neutrons
12. What factor determines that an oxygen
atom can form two covalent bonds while a
carbon atom can form four?
The number of electrons in the outer shell
Carbon has 4
Oxygen has 6
Honors 6.2 assessment
1. What is the relationship between a
chemical bond and a chemical reaction?
Chemical bonds are create or broken by
chemical reactions
2. Why must chemical equations be
balanced?
Because the law of conservation of mass
states that matter cannot be created or
destroyed; matter can only change forms
3. Practice balancing equations.
6K + B2O3 -> 3K2O + 2B
HCl + NaOH -> NaCl + H20
4. What are enzymes?
Special proteins that act as a catalyst to
speed up the rate of a biological reaction.
5. What effect does an enzyme have on a
chemical reaction?
It lowers the activation energy of the
reaction so the rate of the reaction speeds
up
6. Identify the parts of this chemical reaction:
A+B

AB
Reactants
Products
7. Why do the number of atoms of
reactants have to equal the number of
atoms of products formed?
Because of conservation of mass
8. Compare and contrast the substrate and
active site.
Both are part of enzyme substrate complex
active site – specific place where a substrate
binds on an enzyme
substrate – reactant of an enzyme-catalyzed
reaction
9. Identify and describe factors that can
influence enzyme activity.
Temperature, pH, and other substances
6.3 assessment
1. Distinguish between solutions and
suspensions. Give an example of each.
Solutions are mixtures that has substances
evenly mixed throughout (homogeneous).
Example: salt water.
Suspensions are heterogenous mixtures
that separate over time. Example: sand
and water.
2. Relate the structure of water to its
ability to act as a solvent.
Water is a polar molecule meaning it has
unequal charges. Positive charges are
attracted to negative charges on other
water molecules and other solutes.
3. Baking soda is a basic substance.
Describe the effect of baking soda on the
H+ ion concentration of stomach contents
with pH 4.
The baking soda will buffer the H+ ions
because it has more OH- ions. Therefore,
the substance will be less acidic and the pH
will rise.
4. If you add hydrochloric acid to water,
what effect would this have on the H+ ion
concentration? On the pH?
Increase the H+ ions but decrease the pH
number
5. What is the relationship between
a. solution----mixture
A solution is a type of mixture
b. pH-----buffer
Buffer is a substance that is added to a
solution to adjust H+ so that pH is changed
be more acidic or basic
c. acid---base
Acids and bases can both be measured by
concentration of H+ through pH scale.
The more H+ there are, the more acidic
the solution. The less H+, the more basic
the solution.
d. solvent---solute
A solute is dissolved by a solvent.
e. polar molecule---hydrogen bond
A polar molecule is able to form hydrogen
bonds because of the unequal charges
around the molecule.
6. Hydrochloric acid (HCl) is a strong acid.
What ions are formed when HCl dissolves
in water?
H+ and ClWhat effect of HCl on the pH of water?
It would decrease the pH, because of the
increase in H+ ion concentration
7. Compare and contrast adhesion and
cohesion.
Water is cohesive and adhesive
Cohesive means the water molecules stick
to each other
Adhesive means the water molecules stick
to other substances
8. Why is water considered the universal
solvent?
Because it will mix with more substances
than any other solvent
9. Give an example of a homogenous and
heterogenous mixture.
Homogenous – food coloring and water
Heterogenous – fruit salad
6.4
1. What is the name of the element that is
found in all living things?
carbon
2. How many bonds can this element’s
atom form with other atoms?
four
3. What kind of bond does it form?
covalent
4. What is the name of the type of
chemistry that studies only this element?
organic
5. What is a macromolecule?
A giant molecule made of hundreds or
thousands of smaller molecules
6. What are some other names that are
used in place of macromolecules?
Polymers, organic molecules
7. What is a monomer?
small molecules that can join with other
small molecules to make larger molecules (
macromolecules)
8. What is polymerization?
process of making
macromolecules/polymers by joining
smaller compounds together
9. What are the four major categories of
macromolecules?
carbohydrates, lipids, proteins, and nucleic
acids.
10.What monomer makes up the
macromolecule carbohydrate?
monosaccharide
11.What elements make up a
carbohydrate?
Carbon, hydrogen, oxygen
12. What is it called when you have 2
monosaccharides together?
dissacharide
What about 100?
Polysaccharide
13. One of the functions of a carbohydrate
is to store energy. What are the two types
of polysaccharides discussed that store
energy?
Starches and glycogen
14. Which types of polysaccharides provide
structural support to organisms?
Cellulose and chitin
15. What is the formula for a carbohydrate?
—(CH2O)n
16. Give some examples of lipids.
Fats, oil, & waxes
17. What is the monomer for a lipid.
Fatty acid and glycerol
18.Lipids are nonpolar. What does that
mean?
That this molecule has equal charges around
it therefore; lipids do not mix well with
other substances
19. What is a phospholipid and where can it
be found?
A lipid joined to a lipid molecule; found in
the cell membrane; doesn’t mix well with
water so it makes a good barrier for the cell
20.What are the elements found in lipids?
Carbon and hydrogen
21. What is a saturated fat?
lipids that have tail chains made up of only
single bonds between the carbon atoms.
22.What is an unsaturated fat?
Lipids that have tail chains with at least one
double bond between the carbon atoms.
23. What is a polyunsaturated fat?
A lipid with more than one double bond
between the carbon bonds
24.What are the monomers for the
macromolecule protein?
Amino acids
25. What are the elements found in
proteins?
Carbon, hydrogen, oxygen, sulfur and
nitrogen
26. What are the components of an amino
acid? There are 5.
Central carbon, hydrogen, carboxyl group
COOH, variable group, and an amino group
NH3
27. How many different amino acids are
there?
20
28.Why do proteins have so many more
functions than any of the other
macromolecules?
• Diversity of amino acids
• 4 levels of organization