Download Name: 1) The modern model of the atom is based on the work of A

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Name: ____________________________________________
1)
The modern model of the atom is based on the work of
A) one scientist over a long period of time
C) one scientist over a short period of time
B) many scientists over a short period of time
D) many scientists over a long period of time
2)
Which sequence represents a correct order of historical developments leading to the modern model of the
atom?
A) most of the atom is empty space ‚ the atom is a hard sphere ‚ electrons exist in orbitals outside the
nucleus
B) the atom is a hard sphere ‚ most of the atom is empty space ‚ electrons exist in orbitals outside the
nucleus
C) the atom is a hard sphere ‚ electrons exist in orbitals outside the nucleus ‚ most of the atom is
empty space
D) most of the atom is empty space ‚ electrons exist in orbitals outside the nucleus ‚ the atom is a
hard sphere
3)
The modern model of the atom shows that electrons are
A) found in regions called orbitals
B) orbiting the nucleus in fixed paths
C) combined with neutrons in the nucleus
D) located in a solid sphere covering the nucleus
4)
In the modern wave-mechanical model of the atom, the orbitals are regions of the most probable location
of
A) protons
B) positrons
C) electrons
D) neutrons
5)
In the wave-mechanical model, an orbital is a region of space in an atom where there is
A) a circular path in which electrons are found
B) a high probability of finding a neutron
C) a circular path in which neutrons are found
D) a high probability of finding an electron
6)
Subatomic particles can usually pass undeflected through an atom because the volume of an atom is
composed of
A) protons
C) an uncharged nucleus
B) largely empty space
D) neutrons
7)
Which conclusion is based on the "gold foil experiment" and the resulting model of the atom?
A) An atom is mainly empty space, and the nucleus has a positive charge.
B) An atom has hardly any empty space, and the nucleus has a positive charge.
C) An atom is mainly empty space, and the nucleus has a negative charge.
D) An atom has hardly any empty space, and the nucleus has a negative charge.
8)
Which particles are found in the nucleus of an atom?
A) protons and electrons
B) electrons, only
C) protons and neutrons
D) neutrons, only
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9)
Which two particles have approximately the same mass?
A) proton and neutron
C) neutron and electron
B) neutron and positron
D) proton and electron
10)
Which statement is true about a proton and an electron?
A) They have different masses and the same charges.
B) They have the same masses and different charges.
C) They have the same masses and the same charges.
D) They have different masses and different charges.
11)
Which statement best describes electrons?
A) They are negative subatomic particles and are found surrounding the nucleus.
B) They are positive subatomic particles and are found in the nucleus.
C) They are positive subatomic particles and are found surrounding the nucleus.
D) They are negative subatomic particles and are found in the nucleus.
12)
An electron has a charge of
A) +1 and a smaller mass than a proton
B) -1 and a smaller mass than a proton
C) +1 and the same mass as a proton
D) -1 and the same mass as a proton
Which subatomic particle has no charge?
A) beta particle
B) neutron
C) alpha particle
13)
14)
All atoms of a given element must contain the same number of
A) protons plus neutrons
C) protons
B) electrons plus neutrons
D) neutrons
15)
The atomic number of an atom is always equal to the number of its
A) neutrons, only
C) protons plus electrons
B) protons plus neutrons
D) protons, only
16)
What is the total number of protons in the nucleus of an atom of potassium-42?
A) 39
B) 15
C) 19
D) electron
D) 42
17)
Which statement best describes the nucleus of an aluminum atom?
A) It has a charge of +13 and is surrounded by a total of 13 electrons.
B) It has a charge of +13 and is surrounded by a total of 10 electrons.
C) It has a charge of -13 and is surrounded by a total of 10 electrons.
D) It has a charge of -13 and is surrounded by a total of 13 electrons.
18)
Which notation represents an atom of sodium with an atomic number of 11 and a mass number of 24?
A)
B)
C)
D)
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19)
The atomic mass of an element is the weighted average of the masses of
A) all of its radioactive isotopes
C) its two least abundant isotopes
B) all of its naturally occurring isotopes
D) its two most abundant isotopes
20)
Which statement best explains why most atomic masses on the Periodic Table are decimal numbers?
A) Atomic masses are an estimated average of the artificially produced isotopes.
B) Atomic masses are determined relative to an H-1 standard.
C) Atomic masses are determined relative to an O-16 standard.
D) Atomic masses are a weighted average of the naturally occurring isotopes.
21)
The number of neutrons in the nucleus of an atom can be determined by
A) subtracting the atomic number from the mass number
B) subtracting the mass number from the atomic number
C) adding the atomic number to the mass number
D) adding the mass number to the atomic mass
22)
An atom of helium-4 differs from an atom of lithium-7 in that the atom of helium-4 has
A) one more neutron
C) two less protons
B) one more proton
D) two less neutrons
23)
The nucleus of an atom of K-42 contains
A) 23 protons and 19 neutrons
B) 19 protons and 42 neutrons
C) 19 protons and 23 neutrons
D) 20 protons and 19 neutrons
24)
Atoms of the same element that have different numbers of neutrons are classified as
A) isomers
C) isotopes
B) charged atoms
D) charged nuclei
25)
Which two notations represent atoms that are isotopes of the same element?
and
C)
and
A)
B)
26)
27)
28)
and
D)
and
What is the total number of electrons found in an atom of sulfur?
A) 32
B) 16
C) 6
As an atom becomes an ion, its mass number
A) increases
B) decreases
D) 8
C) remains the same
When a lithium atom forms an Li+ ion, the lithium atom
A) loses an electron
C) loses a proton
B) gains a proton
D) gains an electron
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29)
30)
What is the total number of electrons in a Cr3+ ion?
A) 24
B) 27
C) 18
D) 21
How many electrons are in an Fe2+ ion?
A) 24
B) 28
C) 56
D) 26
31)
What is the total number of electrons in the outermost shell of a phosphorus atom in the ground state?
A) 1
B) 2
C) 3
D) 5
32)
What is the total number of valence electrons in an atom of sulfur in the ground state?
A) 6
B) 8
C) 3
D) 4
33)
In comparison to an atom of
in the ground state, an atom of
A) three more neutrons
B) three fewer neutrons
in the ground state has
C) three more valence electrons
D) three fewer valence electrons
34)
What is represented by the dots in a Lewis electron-dot diagram of an atom of an element in Period 2 of the
Periodic Table?
A) the number of protons in the atom
B) the number of valence electrons in the atom
C) the number of neutrons in the atom
D) the total number of electrons in the atom
35)
Which Lewis electron-dot structure is drawn correctly for the atom it represents?
A)
B)
C)
D)
Which Lewis electron-dot diagram represents a boron atom in the ground state?
B)
C)
A)
D)
36)
37)
When compared with the energy of an electron in the first shell of a carbon atom, the energy of an electron
in the second shell of a carbon atom is
A) less
B) greater
C) the same
38)
An electron in an atom moves from the ground state to an excited state when the energy of the electron
A) increases
B) decreases
C) remains the same
39)
Compared to an atom of hydrogen in the ground state, an atom of hydrogen in the excited state has
A) released energy, only
C) neither released nor absorbed energy
B) both released and absorbed energy
D) absorbed energy, only
40)
Which electron transition represents a gain of energy?
A) from 3rd to 2nd shell
B) from 3rd to 1st shell
C) from 2nd to 3rd shell
D) from 2nd to 1st shell
41)
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An atom of oxygen is in an excited state. When an electron in this atom moves from the third shell to the
second shell, energy is
A) emitted by the electron
C) absorbed by the nucleus
B) emitted by the nucleus
D) absorbed by the electron
42)
When the electrons of an excited atom return to a lower energy state, the energy emitted can result in the
production of
A) isotopes
C) protons
B) alpha particles
D) spectra
43)
What is the electron configuration of a sulfur atom in the ground state?
A) 2-4
B) 2-8-4
C) 2-8-6
D) 2-6