Download Chemical and Physical Property Unit Test

8th grade integrated science
Standard 1, Objective 1
Multiple Choice
a1. Which of the following is an example of a chemical property of water? It
A.
B.
C.
D.
boils at 100 C
is transparent
has no odor
reacts with calcium
a2. Which of the following is an example of a physical property of hydrogen? It
A.
B.
C.
D.
is less dense than air
reacts with oxygen
is highly flammable
forms hydrochloric acid
a3. Which of the following is true of chemical properties? They
A.
B.
C.
D.
describe the phase the substance is in
are measurements of the size or mass of the substance
explain how the substance reacts with other substances
predict how much of the substance is found in the universe.
Use the information in this table to answer the next two questions.
Hydrogen Gas
Properties of 4 substances
Density
Phase at room
Reaction with
temperature
water
.00009 g/ml
Gas
None
Sodium
.97 g/ml
Solid
Carbon
Argon
2.2 g/ml
.002 g/ml
Solid
Gas
Substance
a6. Which substance showed no chemical change?
A.
B.
C.
D.
hydrogen
sodium
carbon
argon
a7. Which of the tests measured physical properties?
A. density, reaction to flame
B. density, phase
C. reaction to flame and water
D. phase, reaction to water
Violent bubbling
reaction
None
None
Reaction to
flame
Burns
explosively
Burns
explosively
Burns slowly
None
Use this list to answer the next two questions:
common substances: salt, water, air, sugar, iron, paper, plastic milk carton,
gasoline
b8. Which of these substances would be classified as highly flammable?
A.
B.
C.
D.
salt, air
iron, plastic
paper, gasoline
water, sugar
b9. Which of these substances would be classified as flexible?
A.
B.
C.
D.
salt, iron
water, paper
sugar, gasoline
paper, plastic
b10. Marie Curie was the first scientist to purify and name the element Radon. What
must she have done to describe Radon to other scientists?
A.
B.
C.
D.
discovered its chemical and physical characteristics
tell them how much she enjoyed finding it in the ore.
found pictures in a book to share with them.
looked all over the world for other samples of pure Radon
b11. A student finds an interesting substance and tests it several ways. The substance
is a liquid, dark in color and does not react with baking soda or metals. The student
looks on the Internet to see if he can find out what it is. How is the student using
scientific methods?
A.
B.
C.
D.
he is looking for and finding new things.
he is using the Internet to look up information
he is classifying a substance based on its characteristics
he is doing an experiment with a controlled variable.
The following information was found in a search for information on “gold”. Use it
to answer the next three questions:
Gold
Gold is the most malleable metal. A single gram can be beaten into a sheet of one square
meter. Gold leaf can be beaten thin enough to allow light to shine through it.
Gold is a good conductor of heat and electricity, and is not affected by air and other
chemicals. Heat, moisture, oxygen, and most corrosive agents have very little chemical
effect on gold, making it useful for use in coins and jewelry. Because of its low reactivity,
pure, metallic gold is tasteless.
In addition, gold is very dense, a cubic centimeter weighing 19.3 g. By comparison, the
density of lead is 11.3 g/cm³.
c12. Which of the following is a chemical property of gold?
A.
B.
C.
D.
does not react with most other chemicals.
is very malleable, can form thin sheets
is very dense
it forms beautiful and valuable jewelry.
c13. Thin sheets of gold are often used to cover clay statues to create the appearance
of the statue being made of solid gold. Which property of gold allows it to be used this
way?
A.
B.
C.
D.
Taste
Density
Reactivity
Malleability
c14. Which properties of gold make it valuable for use in computers and satelites?
A.
B.
C.
D.
it is yellow in color and has no taste.
it conducts electricity and not affected by other chemicals
it forms thin sheets and has a high density
it can be reused to make jewelry and other valuable objects.
Standard 1, objective 2
a1. An ice cube is left on a table for an hour. What evidence shows a physical change takes
place?
A.
B.
C.
D.
It turns into a different substance.
It gives off carbon dioxide
It melts into water
It bubbles and gives off gas
a2. Salt is mixed with water and stirred. Is this a physical or chemical change?
A.
B.
C.
D.
It is chemical because a new substance, saltwater, has been formed.
It is chemical because a gas, water vapor, is given off.
It is physical because the salt has turned into a gas.
It is physical because it is easily reversible.
a3. A balloon is placed in a freezer and left overnight. Which would be evidence that a physical
change occurred when the freezer was opened the next day? The balloon
A.
B.
C.
D.
cannot return to it’s original shape
has shrunk in size
cannot be found
is giving off a new gas
b4. An iron nail left outdoors for a year undergoes a chemical change. What evidence would
visible? The nail would be
A.
B.
C.
D.
bent
rusty
buried in soil
sharper
b5. What hazards exist when mixing unknown chemicals?
A.
B.
C.
D.
A physical change may make them less useful
A physical change may make them change phase.
A chemical change may create heat and expansion.
A chemical change may alter the colors.
Use the following data to answer the next two questions.
An experiment with rock salt used three beakers. Each had 100 ml of water and 25 g of salt
added. Beaker A was left alone and Beaker B and C were changed. The time needed to dissolve
the salt was measured.
Beaker
A
B
C
Change
None
Stirred with spoon
Heated on hot plate
Time to dissolve
6 hours (360 minutes)
8 minutes
25 minutes
b6. Which of the following is the best question for this experiment?
A.
B.
C.
D.
What happens when you place 25 grams of salt into 100 mL of water?
What changes the speed it takes salt to dissolve?
What happens to salt when it dissolves in water?
When does salt and water change chemically?
b7. Which conclusion best sums up this experiment?
A.
B.
C.
D.
Salt will dissolve in water if left alone.
Heating and stirring are equally important if you want to dissolve salt.
Salt will dissolve in water quickly if the size of the salt particles is smaller.
Salt will dissolve more quickly if it is stirred than if it is heated or left alone.
b8. A student puts out fire on the stove by dumping baking soda on the flame. How has the
student used scientific knowledge in his daily life?
A.
B.
C.
D.
He knew a physical property of baking soda is that it doesn’t melt
He knew a chemical property of baking soda is that it doesn’t burn
He knew a chemical property of baking soda is that it dissolves in water
He knew a physical property of baking soda is that it is white in color
b9. How do you know when a chemical reaction has occurred?
A.
B.
C.
D.
a new substance has formed; it would be hard to reverse
a phase change has occurred and heat was given off.
the substance changes size, shape, texture and mass
the mass of the reactants is changed into energy that is given off
10. How does a burning fire consume atmospheric oxygen differently than a nail rusting?
A.
B.
C.
D.
A fire uses oxygen much more rapidly
Rusting requires a special form of oxygen
A fire does not need as much oxygen as rusting
Rusting is a chemical change, fire is not
Use this information to answer the next two questions.
Reactions Involving Atmospheric Oxygen
Reaction
Rust
Fire
Respiration
Photosynthesis
Speedmeasured in
Months
Minutes
Hours
Hours
Reactants
Products
Metal, often water
Fuel (carbon compounds)
Food (carbon compounds)
Carbon dioxide, water
Rust
Carbon dioxide, water
Carbon dioxide, water
Sugar, oxygen
11. What is the main difference between fire and respiration?
A.
B.
C.
D.
how quickly they happen
the fuels that are burned
the products
they are identical
12. How is rust different from the other three reactions?
A.
B.
C.
D.
It happens in the out-of-doors.
It uses water.
It involves metals.
It cannot be measured.
13. Scientists have developed special paints for the undersides of ships at sea. What problem are
they trying to correct?
A.
B.
C.
D.
flexibility of steel beams
dissolving of plastic parts
rusting of metal parts
melting of ship engines
d14. Charles Goodyear accidentally spilled sulfur on latex rubber and discovered a way to make
the rubber more elastic. What does his discovery show about science?
A.
B.
C.
D.
scientific discoveries are made in many ways.
chemical changes use the same set of steps and procedures
physical changes are random and unpredictable
scientific discoveries are made following specific steps.
d15. A chemical change occurs when an egg cooks. What effect does the chemical change have
on the physical properties of the egg?
A.
B.
C.
D.
the egg is unchanged.
the egg has new physical properties
the egg cannot be measured
the egg has doubled in size.
Standard I, Objective 3
a1. What often happens when a chemical or physical change occurs?
A. changes in mass
B. changes in size
C. changes in energy
D. changes in color
a2. What must often be added to increase the speed or ability of two substances to react?
A. a bigger container
B. adding heat
C. more substances
D. adding water
a3. What kinds of energy are produced by bright fireworks?
A. electricity, steam
B. motion, gravity
C. sound, magnetism
D. light, heat
b5. Which of the following statements best explains why water changes from a liquid to
a gas when heated?
A. The heat energy causes molecules to move faster and they move farther apart. Some
molecules have enough energy to escape the water as a gas.
B. Water turns into a gas when heated because it expands and the container can no
longer hold it. The molecules spill out the sides of the container.
C. The molecules of water change to hydrogen and oxygen. They are gases and escape
from the water.
D. When the water is heated, molecules of gas that are dissolved in it start to escape.
The gas bubbles rise because they are less dense.
b6. The boiling point of water at sea level is 100 degrees Celsius. What phase would
you expect water to be if it were heated to 110 degrees Celcius?
a.
b.
c.
d.
solid, because the molecules are moving more slowly
liquid, because some of the molecules are still boiling at 110 degrees.
gas, all the molecules have enough energy to have escaped at 110 degrees.
plasma, all the molecules have enough energy to glow
c8. What does liquid water need to change into water vapor?
A. heat energy
B. a test tube
C. a thermometer
Use the following graph to answer the next three questions. It shows the
temperature of an ice cube as it is heated.
c9. When would you expect to see liquid water?
A. at 0 minutes
B. any time after 0 minutes
C. any time over 6 minutes
D. between 6 and 24 minutes
c10. What would you expect water to be doing at 95 C?
A. condensing
B. freezing
C. boiling
D. shaking
c11. How would the graph look if the water were heated more rapidly?
A. the line would be the same
B. the line would rise more steeply
C. the line would rise more slowly
D. the line would go up, then down, then up.
c12. A student is making soup on a stovetop. He brings it to a boil and then turns down
the heat so it barely continues to boil. Will the soup cook more quickly if he turns the
heat back up?
A. no, once the soup boils, it cannot change temperature until solids form.
B. no, once the soup reaches its boiling point the temperature will not rise.
C. yes, the temperature will rise and the vegetables will cook more rapidly.
D. yes, the temperature must be as high as possible to move the molecules.
d14. A bag containing several chemicals is used for sports injuries. When the chemicals
are combined, the bag becomes cold. What is this evidence of?
A. physical change
B. chemical change
C. nuclear change
Use this information for the next two questions.
A Reaction
tem perature (C)
Students place a thermometer in a
beaker of vinegar and begin to record
the temperature. When they added
a spoonful of baking soda, a bubbling
reaction occurred. They continued to
record the temperature and
created the graph below.
30
28
26
24
22
0
1
2
3
4
5
6
7
tim e (min)
d15. What evidence from the graph shows that the baking soda was added to the vinegar
at minute 2?
A. the temperature dropped
B. the temperature rose
C. the temperature stayed the same
D. the time was recorded in minutes.
d16. How can this reaction be described in terms of energy?
A. energy is changed to matter in the gas bubbles.
B. energy is taken in by the reaction
C. energy is given off as heat by the reaction
D. energy is taken in by the rising bubbles.
e17. A candle manufacturing company is finding that boxes of freshly made candles are
melting in a room that should be cool enough for them to stay solid. A storeroom clerk
suggests that they try adding fewer candles to each box. They try it and discover that it
solves the problem. How has the clerk used scientific methods?
A.
B.
C.
D.
by finding better ways to store candles
by making a hypothesis and testing it.
by observing how many boxes are in the storeroom.
by working hard for the company.
e18. Students were asked to design an experiment that added or removed energy to a
chemical reaction. Which of the following hypothesis would be found in an experiment
that tested this?
A. If we heat water and change it to a gas, then it can be collected into a liquid
B. If we heat an ice cube, then it will melt faster.
C. If we heat water and add salt, then the salt will dissolve faster.
D. If we heat vinegar and add baking soda, then it will react faster.
Use these data to answer the next two questions.
Students heated a strip of magnesium in a flame. They held it with tongs and timed the
reaction.
Time (min)
0
1
2
3
Observations
No change
No change
Burning brightly
Burned out
e19. Which question did the students test?
A.
B.
C.
D.
How long does it take for magnesium to get hot enough to burn?
Does magnesium burn?
How much magnesium will burn once it starts?
What does magnesium turn into when it burns?
e20. What conclusion could most accurately be made from these results?
A.
B.
C.
D.
Magnesium burns.
Magnesium needs to heat up before it will burn.
Magnesium needs 2 minutes to gather enough oxygen to burn.
Magnesium is very bright and fun to burn.
Objective 4
a1. Vinegar is added to baking soda and bubbles of carbon dioxide rapidly form. A
cloudy liquid is left behind. What are products in this chemical reaction?
A.
B.
C.
D.
vinegar and the cloudy liquid
vinegar and baking soda
carbon dioxide and baking soda
carbon dioxide and the cloudy liquid
a2. How does the number and kind of atoms involved as reactants in a chemical reaction
compare to the number and kind of atoms in the products?
A.
B.
C.
D.
there are more atoms that react
there are more atoms that are produced
there are the same number and kind of each
it varies from one reaction to another
6 CO2 + 6 H2O
C6H12O6 + 6O2
a3. Which are the reactants in this reaction?
A.
B.
C.
D.
C6H12O6
C6H12O6 + 6O2
6 CO2
6 CO2 + 6 H2O
Use this equation to answer the next three questions:
Lead Nitrate + Sodium Iodide
Sodium Nitrate + Lead Iodide
(Both dissolved in water forming
clear solutions)
(dissolved in water) (bright yellow solid)
a4. What are the products in this equation?
A.
B.
C.
D.
lead nitrate, sodium nitrate
sodium iodide, lead iodide
sodium nitrate, lead iodide
lead nitrate, sodium iodide
c5. What has happened to the atoms of the reactants?
A.
B.
C.
D.
They have recombined to form the products.
They have changed into new atoms.
They have new names and places.
Some have been lost to the environments.
b6. What evidence shows a chemical change took place?
A.
B.
C.
D.
the mass changed
there was liquid involved
a color change occurred
chemicals were used
b7. Our body breaks down food using chemical reactions. What is this process called?
A.
B.
C.
D.
photosynthesis
respiration
combustion
production
b8. A biologist studies photosynthesis and describes it as a biological process. A
chemist studies photosynthesis and describes it as a chemical reaction. Which scientist is
correct?
A.
B.
C.
D.
both, they use different terms but agree on the reactants and products.
neither, if scientists don’t agree, then conclusions cannot be made.
the chemist because photosynthesis has both reactants and products.
the biologist because it is a biological process occurring in cells.
c9. If four carbon atoms combine with oxygen to form carbon dioxide molecules, how
many carbon atoms will be found in the product?
A.
B.
C.
D.
one
two
three
four
Use this information to answer the next two questions:
Students measure 2.0 g of baking soda and 5.0 g of vinegar. They mix them together in a
beaker and watch as bubbles form. The mass of the resulting liquid is 6.7 g.
c10. Based on the Law of Conservation of Mass, what should the mass of the gas that
escaped be?
A.
B.
C.
D.
.3 g
.5 g
.7 g
6.7 g
c11. How should students redesign this experiment for better accuracy?
A. use more baking soda and less vinegar
B. be more precise in the use of the triple-beam balance
C. use different substances so that the reaction is slower
D. trap and find the mass of the escaping gasses
c12. The Law of Conservation of Mass states that matter is not gained or lost in a
chemical reaction. Which of the following correctly restates this law? In a chemical
reaction
A. matter is gained and lost but energy is conserved.
B. the amount of mass is equal to the sum of the reactants and products.
C. matter is gained and lost in depending on how much energy is added.
D. the amount of mass of the reactants will equal the mass of the products
c13. A student uses clay to model the conservation of mass. First, she finds the mass of
a block of clay on a balance. Then she molds the clay into a different shape, without
adding or removing clay. She masses it again. How will her results model this law?
A.
B.
C.
D.
they will show that the shape has changed, but the mass is the same.
they will show that the shape has changed and the mass has also.
they will show the changing shape has changed the mass of the clay.
they will show that the larger the shape, the greater the mass.
Use these data to answer the next four questions:
Students added vinegar to baking soda and collected the gas. They timed how much gas
formed in 30 seconds to measure the speed of the reaction. Then they tried three
additional tests. Each test was repeated 4 times.
Test
1
2
3
4
Baking
soda
1 gram
1 gram
2 grams
1 gram
Vinegar
20 mL
40 mL
20 mL
20 mL
Conditions
25C all reactants
25C all reactants
25C all reactants
Vinegar heated to 60C
Average
amount of gas
formed in 30
seconds.
70 mL
80 mL
70 mL
100 mL
d14. Which test should be considered the control?
A. 1
B. 2
C. 3
D. 4
d15. Which variable was changed in test #2?
A. the amount of baking soda
B. the amount of vinegar
C. the temperature of the vinegar
D. the amount of gas produced
d16. What should the students conclude about changing the amounts of reactants?
Changing the amount of reactants
A. changes the speed the reaction
B. does not change the speed of the reaction
C. might change the speed of the reaction
D. changes the types of products formed