Mr. Storie
20S Science
20S SCI FINAL EXAM REVIEW KEY:
Final Exam Review
CHEMISTRY PROBLEMS
1. Explain how do determine the number of protons in an atom.
Look at the element on the periodic table – the atomic number is the number of protons.
2. Create an example and explain how to name a covalent compound.
1(Name of first non-metal + prefix)
+ 2(Stem name of second non-metal + ”ide” ending + prefix)
NO2 – nitrogen dioxide
H2O – dihydrogen monoxide
3. Explain the difference between covalent and ionic compounds. Give specific examples.
Ionic – between metal and nonmetal, one gives electron, one takes electron, both to have filled outer
shell, transfer of electrons forms ions, stay bonded through attraction.
NaCl  Na+ ClCovalent – between 2 nonmetals, sharing of electrons so both seem to have full outer shells. No ions
formed, bonded together by continued sharing.
H2O  H:O:H
4. Name 5 families on the periodic table and list some of there properties.
1. Alkali metals – very reactive, contain 1 valence electron, metals, form ionic bonds with a charge of
+1.
2. Alkaline Earth – less reactive, contain 2 valence electrons, metals, form ionic bonds with a charge
of +2.
3. Chalcogens – less reactive, contain 6 valence electrons, non-metals, form ionic bonds with a charge
of -2, or covalent bonds, and some diatomic.
4. Halogens – very reactive, contain 7 valence electrons, non-metals, form ionic bonds with a charge of
-1, covalent bonds and some diatomic.
5. Noble gases – not reactive, usually form no bonds, have 8 valence electrons and a full outer shell.
5. Create an example for each of the following reaction types:
a. Addition (synthesis)
2 Na (s) + Cl2 (g)  2 NaCl (s)
b. Decomposition
2 H2O (l)  2 H2 (g) + O2 (g)
c. Single replacement
CuSO4 (aq) + Al (aq)  Cu (s) + Al2(SO4)3 (aq)
d. Double replacement
NaNO3 (aq) + KCl (aq)  NaCl (aq) + KNO3 (aq)
e. Combustion
CH4 (g) + 2 O2 (g)  2 H2O (g) + CO2 (g)
Mr. Storie
20S Science
Final Exam Review
6. Explain the term diatomic and name the molecules that show this property.
2 – identical atoms combining in a covalent bond to fill their valence shell. Diatomic atoms are highly
reactive and bond to each other when nothing else is available.
I2 H2 N2 Br2 O2 Cl2 F2
7. Name 4 characteristics for acids and 4 characteristics for bases
Acids – sour, contain H+, turn blue litmus red, corrosive, low pH
Base – bitter, contain OH-, turn red litmus blue, slippery, high pH
8. Describe a neutralization reaction in a chemical formula. Label all compounds.
NaOH + HCl  H2O + NaCl
Base
Acid
Water Salt
9. Draw a Bohr diagram for potassium and fluorine.
10. Write formulas for the following and label as covalent or ionic:
a. Carbon tetrachloride
CCl4 - covalent
b. Iron (III) sulfide
c. Sodium nitride
Fe2S3 - ionic
Na3N - ionic
d. Diphosphorous trioxide
P2O3 - covalent
e. Berellium Sulfide
BeS - ionic
11. Name the following and label as covalent or ionic:
a. N2O5
dinitrogen pentoxide - covalent
b. SiO
Silicon monoxide - covalent
c. Li2O2
lithium oxide - ionic
d. Cr2O3
chromium (III) oxide - ionic
e. ZnO
zinc oxide - ionic
Mr. Storie
20S Science
12. Balance the following reactions and classify the reaction type:
a. 2 H2 + O2  2 H2O - synthesis
Final Exam Review
b. 2 BCl3  2 B + 3 Cl2 - decomposition
c. CH4 + 2 O2  CO2 + 2 H2O - combustion
d. Zn + PbO  ZnO + Pb - single displacement
e. 2 NaCl + CaBr2  CaCl2 + 2 NaBr - double displacement
f. Fe2O3 + 3 H2  2 Fe + 3 H2O - single displacement
g. 2 NaCl  2 Na + Cl2 - decomposition
ECOSYSTEMS PROBLEMS
1. Use your dictionary to fill in the blank space of each sentence with the most appropriate word:
a. Plants or producers take carbon dioxide from the atmosphere to use in the process called photosynthesis.
b. Carbon dioxide released to the atmosphere through the burning of fossil fuels is called combustion.
c. Denitrification is the name for the process in which bacteria convert dead matter back into N2 in the
atmosphere.
d. Nitrogen fixation is the process where bacteria convert atmospheric nitrogen into nitrate and ammonia.
e. During photosynthesis, glucose are produced and oxygen gas is released into the atmosphere.
f. Both natality and immigration occur to increase the population size.
g. When members of a population leave to a new area, this is called emmigration.
h. The maximum number of a species that can be supported by the ecosystem is referred to as carrying
capacity.
i. Bacteria in the soil act as the decomposers in the food web.
j.
An open-population allows for migration of individuals, as well as, natality and mortality.
k. Unlike cows or wolf, humans would be described as omnivores, based on their diet.
l. The cycling of nitrogen, carbon and oxygen that occurs on earth is collectively known as
biogeochemical cycles.
m. A pyramid shaped measure of the mass of dry matter contained in a group of living things is pyramid of
biomass.
Mr. Storie
20S Science
Final Exam Review
n. A species that is close to extinction is endangered.
o. A species that is not in immenent danger of extinction, but is at risk because of low or declining numbers
is vulnerable.
p. Racoons will eat almost anything. They are most accurately called scavengers.
q. If you consume only peanuts you would be a primary consumer / herbivore.
2. Construct a food chain. Include one species from 4 different trophic levels: Tertiary consumer, primary
consumer, producer and secondary consumer. Label each level with as much detail as you can.
3. Use a diagram and one example to explain the concept of bioaccumulation.
4. Explain how the following are density dependent or density independent factors:
a. Competition
DD – increase in population increase competition for resources.
b. Disease
DD – increase in population increases transmission rates of disease.
c. forest fire
DI – destroys land and resources making unsuitable for all regardless of size.
d. pollution
DI – destroys resources, affects food webs, regardless of size.
Mr. Storie
20S Science
Final Exam Review
5. Briefly describe (or draw pictures of and label) the major steps in the:
a. carbon cycle
b. nitrogen cycle
PHYSICS PROBLEMS
1. Explain the connection between momentum and impulse using an example of catching a fastball from a
pitcher in baseball. Include formulas.
Baseball has momentum (p = mv). To stop it a force must be applied in the opposite direction for a
time, called an impulse (I = Ft). The impulse applied will be equal to the change in momentum of the
baseball (Ft = mv). The same magnitude of impulse can be applied as a large force over small time
or a small force over large time – producing the same change in momentum. The catcher will soften
the catch (move hand back with the ball) to increase the time the impulse acts, thus decreasing the
amount of force needed to stop the ball. Since equal and opposite forces apply, the ball then applies
an equally small force to the hand of the catcher (it doesn’t hurt).
Mr. Storie
20S Science
Final Exam Review
2. Explain the forces involved when jumping out of a boat causes the boat to move backwards. Use pictures to
help explain and include the concept unbalanced force and Newton’s Laws.
You push off on the boat causing an unbalanced force on the boat. The boat pushes off on you with
an equal and opposite unbalanced force. Because no other forces are acting on the boat or you, you
move forward towards the dock (jump) with the direction of force and the boat moves in the opposite
direction (out to sea) with the opposite force.
3. Briefly describe each of Newton’s 3 laws of motion. Give an example for each.
1. Law of Inertia – objects tend to resist changes in state of motion directly proportional to size:
pushing a car vs. a chair - the larger object takes more force to overcome inertia.
2. F = ma – Force is directly proportional to the size of the object. Applied force is directly
proportional to the acceleration of the object: pushing chair Lab – more force was required to
accelerate 2 people on the chair the with the same value.
3. Equal and opposite reactions – for each applied force there is an equal and opposite force. Recoil
of the gun - trigger explodes bullet forward with force that is equal and opposite to force applied on
gun by bullet.
4. Calculate the average speed for both the cyclist and the roller coaster
vave = Δd / Δt = 70 km - 0 km / 7 h = 10 km/h
vave = Δd / Δt = 120 m - 0 m / 6 s = 20 m/s
5. Examine each P-T graph below, and describe the following features:
a. Slope of the graph (positive/zero/negative; increasing/constant/decreasing)
b. Speed (increasing/decreasing/constant)
c. Direction of motion (right/left; away/towards observer)
d. Velocity of the object (positive/zero/negative; increasing/constant/decreasing)
A.
B.
d
C.
d
t
D.
d
t
d
t
t
Mr. Storie
A.
B.
C.
D.
20S Science
Final Exam Review
zero, zero (constant), zero, zero
positive increasing, increasing, right away, positive increasing
positive constant, constant, right away, positive constant
negative constant, constant, left towards, negative constant
6. From the above 4 graphs, construct the appropriate V-T and A-T graphs.
7. Using the following dot pattern, explain the motion of the object at each number:
1
2
   
3


4





5
6
7
          
1 – stopped
2 – increasing velocity, accelerating
3 – constant velocity, no acceleration
4 – decreasing velocity, negative acceleration
5 – slower constant velocity, no acceleration
6 – decreasing velocity, negative acceleration
7 – very slow constant velocity, no accerlation
8. Fill in the blanks on the following chart:
Distance
10.5 m
210 m
164 km
Time
4.3 s
8.2 s
1.5 s
Velocity
2.4 m/s
25 m/s
110 km/h
9. Calculate the speed of sound (m/s), given that a clap of thunder is heard by an observer 1.5 km away, 4.6 s
after the lightning that produced the sound is seen.
1.5 km x 1000 m / 1 km = 1500 m
v = Δd/Δt = 1500 / 4.6 s = 326 m/s
10. Calculate the distance in kilometers from Earth to the Moon, given that radio waves traveling at the speed of
light (3.0 x 105 km/s) take 1.28 s to cover this distance.
Mr. Storie
20S Science
v = Δd/Δt
3.0 x 105 km/s (1.25 s) = 384000 km = 380000 km
Final Exam Review
11. A car is leaving the city and traveling north at 15 m/s. As it enters a highway the driver accelerates at + 4.0
m/s2 for 5 s.
a. What is the velocity of the car after 2 s?
a = Δv/Δt
aΔt= v2 - v1
(4.0 m/s2)(2.0 s) = v2 - 15 m/s = +23 m/s
b. What is the final velocity of the car?
a = Δv/Δt
aΔt= v2 - v1
(4.0 m/s2)(5.0 s) = v2 - 15 m/s = +35 m/s
c. Describe how the car’s motion would be different if it had accelerated at – 4.0 m/s2. List the car’s
velocity after the end of this acceleration.
a = Δv/Δt
aΔt= v2 - v1
(-4.0 m/s2)(5.0 s) = v2 - 15 m/s = -5 m/s
slowed down, stopped and began moving in the opposite direction
WEATHER PROBLEMS
1. Define radiation.
2. Define albedo.
3. Isobars on a weather map indicate high and low _________.
4. When theses isobars are close together the winds will be (slow or fast).
5. Warm, light air is associated with ( high or low ) pressure systems.
6. Cold air will (rise or sink).
7. Define convection currents.
8. What causes global wind patterns?
9. Stormy weather is associated with (high or low ) pressure systems.
10. Winds blow from _____ to _______ pressure.
11. Define: front, cold front, warm front.
12. Draw and label a diagram of the 4 layers of the atmosphere (thermosphere, mesosphere, troposphere,
stratosphere)
13. On a map label the main ocean currents that affect North and South America.
14. On a map label the 3 prevailing winds in the northern hemisphere.
15. On a map label the major lines of latitude and the major oceans.