TEST NAME: Chemistry
TEST ID: 633854
GRADE: 08
SUBJECT: Life and Physical Sciences
TEST CATEGORY: My Classroom
Chemistry
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Student: Class:
Date:
1.
The following chemical reaction occurs.
2H2O2 → 2H2O + O2
How many atoms of hydrogen are involved in the reaction?
A.
1
B.
2
C.
4
D.
8
2.
Which best represents a balanced equation?
A.
120 grams of carbon plus 20 grams of oxygen → 200 grams of carbon
dioxide
B.
120 grams of carbon plus 50 grams of oxygen → 200 grams of carbon
dioxide
C.
120 grams of carbon plus 80 grams of oxygen → 200 grams of carbon
dioxide
3.
Which best describes the reactivity of metals when moving from left to
right on the periodic table? A.
They become less reactive.
B.
They become more reactive.
C.
The reactivity remains the same.
D.
The reactivity decreases, then increases.
Chemistry
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4.
A marshmallow is made mostly of sugar and air. When heated in a
microwave oven, a marshmallow increases in size to nearly twice its
normal volume but does not produce any new substances. Which best
describes the change in the marshmallow?
A.
The heated air expands as a physical change occurs.
B.
The heated air expands as a chemical change occurs.
C.
The heated air contracts as a physical change occurs.
D.
The heated air contracts as a chemical change occurs.
5.
Which is true of a chemical equation?
A.
Products and reactants must be balanced.
B.
Subscripts must be used with all products and reactants.
C.
Energy must be included in the beginning of the reaction.
D.
Coefficients must be used with all products and reactants.
6.
Which chemical reaction supports the law of conservation of mass?
A.
H2O → H2 + O2
B.
H2O → 2H2 + O2
C.
H2O → H2 + 2O2
D.
2H2O → 2H2 + O2
7.
Which best describes a solid produced in a solution during a chemical
reaction?
A.
acid
B.
solute
C.
reactant
D.
precipitate
Chemistry
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Which is a substance that is held together by chemical bonds?
8.
A.
element
B.
compound
C.
mixture
D.
solution
9. Look at the equation.
What does the equation show?
A.
heat being added to oxygen
B.
helium mixing with oxygen
C.
heat combining with oxygen
D.
hydrogen and oxygen combining
10.
Which element is a liquid at room temperature?
A.
aluminum
B.
mercury
C.
copper
11.
Which best explains how the atomic size of the elements is arranged in
the periodic table?
A.
The atomic size of the elements decreases from left to right and
decreases from top to bottom.
B.
The atomic size of the elements increases from left to right and
increases from top to bottom.
C.
The atomic size of the elements decreases from left to right and
increases from top to bottom.
12.
When two solutions are combined, a bright red precipitate is formed.
Which is true of the precipitate?
A.
It has a mass greater than the two liquids.
B.
It is formed as a result of a chemical reaction.
C.
It has a higher temperature than the two solutions.
D.
It is formed through a change in physical state of one of the
solutions.
Chemistry
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13.
Which chemical formula is an example of a compound?
A.
O2
B.
2Cl
C.
H2SO4
14.
Liquids placed in a beaker will settle in specific layers. Which physical
property of matter does this illustrate?
A.
density
B.
polarity
C.
solubility
D.
malleability
15.
Which of the samples shown represents an element?
A.
substance 1
B.
substance 2
C.
substance 3
D.
substance 4
16. Two identical containers each hold one liter of water. One container is kept at room temperature as a liquid.
The other container is placed in a freezer and kept as a solid. Which property is most likely to be the same in
both states of matter?
A.
density
B.
mass
C.
shape
D.
volume
17.
What is the relationship between elements with 6, 14, and 82 protons in
their nuclei on the periodic table of elements?
A.
They are in the same group.
B.
They are in the same period.
C.
They have the same atomic mass.
Chemistry
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18.
Which best explains why conservation of mass should be studied in a
closed system?
A.
to prevent the loss of any reactants
B.
to prevent contamination of the products
C.
to prevent the release of any gases produced
D.
to prevent the absorption of heat from the outside
19.
Which is a balanced chemical equation according to the law of
conservation of mass?
A.
CH4 + O2 → CO2 + 2H2O
B.
CH4 + O2 → 2CO2 + H2O
C.
CH4 + 2O2 → CO2 + 2H2O
D.
2CH4 + O2 → CO2 + 2H2O
20.
Max recorded the notes below as he completed an experiment in science
class.
20 grams of a solute was added to 100 grams of a liquid substance.
The solute completely dissolved.
The total mass of the resulting solution was 120 grams after the
experiment was complete.
Which best explains how the law of conservation of mass was
demonstrated in the experiment?
A.
The solute completely dissolved in the liquid.
B.
The liquid was chemically changed by the addition of the solute.
C.
Some of the mass of the solute was lost during the experiment.
D.
The mass of the resulting solution was equal to the mass of the
solute and liquid.
Chemistry
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21. Using a closed system, a student heats 100 milliliters (mL) of distilled water in a flask. The steam from the
water is captured, cooled, and condensed as shown in the diagram.
How much water is most likely collected?
A.
1 mL
B.
10 mL
C.
100 mL
D.
110 mL
22.
Which is true about the compounds carbon monoxide (CO) and carbon
dioxide (CO2)?
A.
The compounds have the same properties because they are both
gases.
B.
The compounds have the same properties because they contain the
same elements.
C.
The compounds have different properties because they are found in
different amounts in the atmosphere.
D.
The compounds have different properties because they contain the
same elements in different quantities.
23.
Which is the best evidence that the creation of a precipitate is the result
of a chemical reaction?
A.
demonstrates gas production
B.
demonstrates a temperature change
C.
demonstrates a new substance has formed
Chemistry
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24. Which of these best describes a change that is physical?
A.
yarn being knitted into a sweater
B.
the engine from a tractor being started
C.
the metal on a bicycle forming rust
D.
grass capturing the energy from sunlight
25.
What general category describes the majority of the elements in the
periodic chart?
A.
metals
B.
liquids
C.
nonmetals
26.
An element is being studied in a lab. The element is nonreactive, but
only has two valence electrons. Which element is being studied?
A.
neon B.
helium C.
oxygen 27. Which of these is a physical change that takes place in a garden?
A.
Insects eat the leaves of a plant for food.
B.
Flowers grow after a summer rain shower.
C.
Earthworms loosen soil as they travel through it.
D.
Leaves convert sunlight to sugar by photosynthesis.
28.
Which is one characteristic of some pure substances?
A.
They cannot be changed into simpler substances.
B.
They can be homogeneous or heterogeneous.
C.
They contain different types of molecules.
29.
Iron filings are thrown into a pile of sand. What is the best way to
separate this mixture?
A.
Use a magnet to pick up the sand.
B.
Sift through the sand for all of the iron.
C.
Use a magnet to pick up the iron filings.
Chemistry
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30.
Helium (He) is used to fill a round balloon at room temperature. Which
best represents the arrangement of helium atoms inside the balloon at
room temperature?
A.
B.
C.
D.
Chemistry
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31.
Which best explains how the periodic table is used to identify properties
of elements?
A.
by the color and shape of the elements
B.
by the number of electrons in the elements
C.
by the group in which the elements are located
32.
Which best describes how the current periodic table is arranged?
A.
by atomic mass
B.
by atomic number
C.
in alphabetical order by element symbol
D.
in numerical order by number of neutrons in the nucleus
33.
Why are certain elements placed into the same column on the periodic
table?
A.
They have the same number of protons in their nuclei.
B.
They have the same number of electrons in their nuclei.
C.
They have the same number of electrons in their outer energy level.
34.
Which element in Period 3 is known to be a highly reactive metal?
A.
sulfur (S)
B.
argon (Ar)
C.
sodium (Na)
D.
scandium (Sc)
35.
Which property is unique for each element?
A.
mass number
B.
atomic number
C.
state of matter
Chemistry
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36.
Which property would be most useful in placing a newly discovered element
in Group 18 (VIIIA) on the periodic table?
A.
reactivity
B.
malleability
C.
conductivity
D.
nonreactivity
37.
Why does reactivity in non­metals most likely increase from left to right in
the periodic table?
A.
atomic radius increases
B.
attraction for electrons increases
C.
attraction for electrons decreases
38.
Which is the most reactive group of nonmetals?
A.
Group 1
B.
Group 5
C.
Group 17
39.
Which would sink first when placed in water?
A.
gold
B.
silver
C.
copper
40.
Sodium (Na), lithium (Li), and potassium (K) are grouped together in one
column on the periodic table. Which property do they share?
A.
soft texture
B.
high reactivity
C.
semiconductivity
D.
gas at room temperature
Chemistry
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41.
Which best describes a row of elements in the periodic table?
A.
column
B.
family
C.
group
D.
period
42.
Which best describes elements that are shiny, malleable, ductile, and
good conductors of heat and electricity?
A.
halogens
B.
metals
C.
metalloids
D.
nonmetals
43.
How are elements on the periodic table organized by their properties?
A.
in groups
B.
by masses
C.
in periods
44. When iron combines with oxygen in a moist environment, rust forms because of a
A.
chemical reaction.
B.
physical reaction.
C.
change in density.
D.
change in temperature.
45.
Which best explains how elements combine in different ways to produce
compounds?
A.
state of matter
B.
chemical reactivity
C.
similar physical properties
D.
matching atomic numbers
Chemistry
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46. Students performed an investigation on how aluminum cans taken to a recycle center were able to be
reused. They found out an aluminum can undergoes which type of change?
A.
a physical change because the can is heated
B.
a chemical change because new metal is formed
C.
a physical change because the material remains the same
D.
a chemical change because an old can is changed into a new can
47. Which is an example of a chemical reaction?
A.
Vinegar added to baking soda forms a gas.
B.
Water evaporates into air.
C.
Sugar dissolves in water.
D.
Corn kernels are crushed to form flour.
48. A group of students observed the formation of bubbles when water boiled. What happened to matter
because of the physical change to the water?
A.
New matter was created in the bubbles.
B.
Old matter was destroyed as the water turned to gas.
C.
Matter was conserved when it changed form.
D.
The composition of the matter changed.
49.
The table shows the solubility of various substances in water.
Solubility of Substances in Water
Solubility Temperature
(in mg/L)
(°C)
Lauric Acid
4.81
25
Folic Acid
1.60
25
Salicylic Acid 2,240
25
6
Ethanol 1.0 x 10
25
Methane
22
25
Substance
Which is the best way to increase the solubility of Folic Acid?
A.
by increasing the volume
B.
by decreasing the volume
C.
by increasing the temperature
50. A beaker contains a sample of water with a mass of 325 grams. The water in the beaker is boiled and
weighed again after it cools. The new mass of the water is 305 grams. In this example of the conservation of
matter in physical changes,
A.
the mass is less after it cools because water has less mass as a gas.
B.
the mass of the water was 305 grams and the mass of the water vapor was 20 grams.
C.
the process of boiling destroyed 20 grams of the water and left 305 grams of water.
D.
the heat energy created by boiling water makes up the rest of the mass.
Chemistry
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51.
A scientist adds sodium acetate to boiling water until it is all dissolved.
Once the solution starts to cool, it becomes solid crystals. Which is
evidence that a chemical reaction has taken place?
A.
There is less liquid.
B.
There is more mass.
C.
A precipitate forms.
52.
Sam finds a block made from an unknown element. Which is the best way
to determine which element was used to create the block?
A.
test the malleability of the block
B.
determine the mass of the block
C.
calculate the density of the block
D.
observe the reaction between the block and a nonmetal
53.
Which equation demonstrates the law of conservation of mass?
A.
Al + 2HCl → AlCl + H
B.
4Al + 2HCl → 2AlCl + H2
C.
2Al + 3HCl → 2AlCl + 3H2
D.
2Al + 6HCl → 2AlCl3 + 3H2
54.
Which products would balance the equation below? CaCl2 + 2Li →
A.
LiCl + Ca
B.
Li2Cl + Ca
C.
2LiCl + Ca
Chemistry
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55.
A sealed test tube containing 8 grams of iron filings and 5 grams of
sulfur is heated until the material in the test tube glows bright red.
Which is true about the reaction?
A.
The product will have a mass of 13 grams.
B.
The product will have a mass less than 13 grams.
C.
The product will have a mass greater than 13 grams.
D.
The mass of the product cannot be determined.
56.
Which equation is balanced according to the Law of Conservation of
Mass?
A.
NaCl + Mg → MgCl2 + Na
B.
2NaCl + Mg → MgCl2 + Na
C.
2NaCl + Mg → MgCl2 + 2Na
57.
One molecule of carbon dioxide (CO2) combines with one molecule of
water (H2O) to make one molecule of carbonic acid. According to the Law
of Conservation of Mass, how many atoms of carbon should be in the
carbonic acid?
A.
1
B.
2
C.
3
58. Which of the following is a correctly written chemical equation that demonstrates the conservation of
mass?
A.
B.
C.
D.
Chemistry
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59.
Which best explains how the chemical reaction shown below follows the
law of conservation of mass?
2H2 + O2 → 2H2O
A.
The hydrogen and oxygen molecules combine to form water.
B.
Hydrogen and oxygen are held together by strong chemical bonds.
C.
There are hydrogen and oxygen atoms on both sides of the equation.
D.
The same number of hydrogen and oxygen atoms are on both sides of
the equation.
60. If 100 grams of vinegar and 5 grams of baking soda are poured in a container, a small amount of gas will be
produced. What will the final mass of the products be if the gas is trapped in the container?
A.
100 grams
B.
104 grams
C.
105 grams
D.
110 grams
Chemistry
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