Name: 
 

8th Grade Review Day 2



Matching
 
 
Match each term with the correct definition.
a.
neutron
h.
half-life
b.
mass number
i.
isotopes
c.
atomic number
j.
transmutation
d.
element
k.
alpha particle
e.
beta particle
l.
proton
f.
electron cloud
m.
radioactive decay
g.
electron
n.
average atomic mass
 

 1. 

matter that is made up of only one kind of atom
 

 2. 

a negatively charged particle that is part of every kind of matter
 

 3. 

a positively charged particle that is present in the nucleus of all atoms
 

 4. 

uncharged particle in the nucleus of an atom
 

 5. 

region surrounding the nucleus in which the electrons move about
 

 6. 

the number of protons in the nucleus of an atom of an element
 

 7. 

atoms of the same element that have different numbers of neutrons
 

 8. 

the number of neutrons plus protons in the nucleus of an atom
 

 9. 

the mass of the mixture of the isotopes for an element
 

 10. 

the release of nuclear particles and energy
 

 11. 

the changing of one element into another element through radioactive decay
 

 12. 

particle consisting of two protons and two neutrons
 

 13. 

a high-energy electron that comes from the nucleus, not from the electron cloud
 

 14. 

the amount of time required for half a sample of a radioactive isotope to decay
 
 
Match each item with the correct statement below.
a.
alkali metals
k.
metals
b.
alkaline earth metals
l.
metalloids
c.
ductile
m.
noble gases
d.
atomic number
n.
nonmetals
e.
actinides
o.
period
f.
group
p.
mass number
g.
halogens
q.
representative elements
h.
hydrogen
r.
semiconductors
i.
lanthanides
s.
transition elements
j.
malleable
 

 15. 

elements that are gases or brittle solids and poor conductors of heat and electricity
 

 16. 

basis for arranging elements in modern periodic table
 

 17. 

able to be hammered into thin sheets
 

 18. 

series of radioactive elements
 

 19. 

a row of elements in the periodic table whose properties change gradually and predictability
 

 20. 

elements that show moderate electrical conductivity
 

 21. 

silvery solids with low densities and low melting points found in Group 1
 

 22. 

elements that show properties of both metals and nonmetals
 

 23. 

elements in Groups 3 through 12 of the periodic table
 

 24. 

only nonmetal in Group 1
 

 25. 

most chemically inactive group of elements
 

 26. 

another name for Group 2 elements
 

 27. 

group of elements that form salts
 

 28. 

most elements fall into this classification
 

 29. 

series of elements that are sometimes called the rare earths
 
 
Classify the elements described below as a metal, nonmetal, or metalloid.
a.
metal
b.
nonmetal
c.
metalloid
 

 30. 

a gas at room temperature
 

 31. 

a poor conductor of electricity
 

 32. 

can be used as a semiconductor
 

 33. 

can be hammered into thin sheets
 

 34. 

has a dull appearance and is brittle
 

 35. 

a transition element
 

 36. 

used for computer chips
 

 37. 

can be drawn out into a thin wire
 

Multiple Choice
Identify the choice that best completes the statement or answers the question.
 

 38. 

____ contain(s) only one kind of atom.
a.
Matter
c.
Chemicals
b.
Elements
d.
Radioactive materials
 

 39. 

A(n) ____ is the basic unit of matter.
a.
electron
c.
atom
b.
molecule
d.
space
 

 40. 

Particles in an atom’s nucleus that do not have an electric charge are called ____.
a.
neutrons
c.
ions
b.
electrons
d.
protons
 

 41. 

The atomic mass of an atom consists of the mass of the ____.
a.
protons and neutrons
c.
neutrons and electrons
b.
protons and electrons
d.
neutrons, protons, and electrons
 

 42. 

In an atom, the electrons can be found in the ____.
a.
nucleus
c.
isotope
b.
neutron
d.
electron cloud
 

 43. 

J. J. Thomson used the fact that ____ charges attract each other in his cathode-ray tube experiment.
a.
like
c.
atomic
b.
neutral
d.
opposite
 

 44. 

The mass number of an isotope is the number of ____.
a.
electrons and protons
c.
neutrons
b.
neutrons and protons
d.
protons
 

 45. 

Isotopes are atoms of the same element that have a different number of ____.
a.
protons
c.
neutrons
b.
electrons
d.
nuclei
 

 46. 

To find the number of neutrons in an isotope, subtract the____.
a.
atomic number from the mass number
b.
mass number from the atomic number
c.
number of isotopes from the mass number
d.
number of protons from the number of electrons
 

 47. 

The most stable isotope of an atom with 12 protons probably has ____ neutrons.
a.
24
c.
6
b.
18
d.
12
 

 48. 

The strong nuclear force holds the ____ together.
a.
protons
c.
nucleus
b.
neutrons
d.
electrons
 

 49. 

Radioactive decay is the release of ____.
a.
radios
c.
nuclear particles and energy
b.
isotopes
d.
light
 

 50. 

A(n) ____ particle consists of two protons and two neutrons.
a.
gamma
c.
beta
b.
alpha
d.
omega
 

 51. 

The changing of one element into another in radioactive decay is called ____.
a.
transmutation
c.
half-life
b.
radiation
d.
a chain reaction
 

 52. 

Radioactive decay can be affected by ____.
a.
the weather
c.
increased pressure
b.
magnetic fields
d.
none of these
 

 53. 

A radioactive isotope has a half-life of 100 years. A sample of 40 g of the isotope will have a mass of ____ g in 200 years.
a.
120
c.
20
b.
40
d.
10
 

 54. 

Tracer elements can be used without danger to people because they have ____ half-lives.
a.
short
c.
strong
b.
long
d.
nonexistent
 

 55. 

A noble gas has ____.
a.
twice as many neutrons as protons
c.
no nucleus
b.
a stable outer energy level
d.
an ionic bond
 

 56. 

At the center of an atom is a nucleus containing ____.
a.
molecules
c.
neutrons and electrons
b.
electrons
d.
protons and neutrons
 

 57. 

When an atom gains an electron and becomes negatively charged, we refer to it as a(n) ____.
a.
negative ion
c.
positive ion
b.
electron
d.
molecule
 

 58. 

A molecule consisting of two hydrogen atoms joined in a covalent bond would be written as ____.
a.
HO2
c.
HYD2
b.
H2
d.
H2O
 

 59. 

For a neutral atom of an element, the number of ____ is always the same.
a.
ions and electrons
c.
neutrons and protons
b.
protons and electrons
d.
atoms and molecules
 

 60. 

Removing electrons that are closer to the nucleus takes ____than removing electrons that are farther away from the nucleus.
a.
more energy
c.
less energy
b.
an equal amount of energy
d.
more time
 

 61. 

A sodium atom that is positively charged is written as ____.
a.
Na–
c.
S+
b.
Na+
d.
Na2
 

 62. 

The bond that forms between atoms when they share electrons is called a(n) ____ bond.
a.
ionic
c.
atomic
b.
covalent
d.
shared
 

 63. 

Atoms form ____ with other atoms and become more stable.
a.
chemical bonds
c.
acids
b.
neutrons
d.
bases
 

 64. 

An ion is an atom that has ____ or ____ an electron.
a.
shared; lost
c.
borrowed; shared
b.
multiplied; divided
d.
gained; lost
 

 65. 

A(n) ____ is a pure substance that contains two or more elements.
a.
molecule
c.
compound
b.
particle
d.
ion
 

 66. 

When a positively charged ion and a negatively charged ion are attracted to each other, the bond they form is referred to as a(n) ____ bond.
a.
ionic
c.
atomic
b.
covalent
d.
shared
 

 67. 

When two or more atoms share electrons unevenly, resulting in a positive charge on one end and a negative charge on the other, they are held together by a(n) ____ bond.
a.
neutral
c.
ionic
b.
polar
d.
nonpolar
 

 68. 

A ____ is a covalent bond involving two pairs of electrons.
a.
double bond
c.
single bond
b.
dioxide
d.
double ion
 

 69. 

A molecule of carbon monoxide, CO, has ____ atoms.
a.
one
c.
two
b.
fourteen
d.
three
 

 70. 

A(n) ____ is a combination of chemical symbols and numbers that tells which elements are present in a molecule and how many atoms of each element are present.
a.
formula
c.
periodic table
b.
electron dot diagram
d.
elemental chart
 

 71. 

A molecule is the neutral particle formed when ____.
a.
an atom is neutral
c.
an atom ionizes
b.
atoms share electrons
d.
atoms share neutrons
 

Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.
 

 72. 

A proton is a positively charged particle present in the nucleus of all atoms. _________________________

 

 73. 

The mass of a proton is much greater than the mass of a neutron. _________________________

 

 74. 

Atoms of the same element can have a different number of neutrons. _________________________

 

 75. 

Dalton believed that the atom was a hard sphere that was the same throughout. _________________________

 

 76. 

J. J. Thomson did experiments that showed that atoms cannot be divided into smaller particles. _________________________

 

 77. 

Rutherford’s experiment showed that alpha particles could pass through foil because most of an atom is neutrally charged. _________________________

 

 78. 

The strong nuclear force can hold the protons of an atom together only if the protons are far apart. _________________________

 

 79. 

Once a living organism dies, the amount of carbon-14 cannot be replaced. _________________________

 

 80. 

The nonmetals are not very important. _________________________

 

 81. 

Silicon and germanium are used in electronics as semiconductors. _________________________

 

 82. 

The element silver is widely used in dentistry. _________________________

 

 83. 

All transition elements are metals. _________________________

 

 84. 

Most of the actinides occur naturally in Earth’s crust. _________________________

 

 85. 

Lithium and sodium are members of the alkali metal family. _________________________

 

 86. 

Bromine and mercury are liquids at room temperature. _________________________

 

 87. 

A period contains elements that have similar properties. _________________________

 

 88. 

Helium, argon, and radon are members of the halogen family. _________________________

 

 89. 

The most active metals are found in the noble gas family. _________________________

 



 
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