Download Chapter 02 The Structure of the Atom and the Periodic Table

Chapter 02 - The Structure of the Atom and the Periodic Table
Chapter 02
The Structure of the Atom and the Periodic Table
Short Answer Questions
1. List the three primary particles found in an atom.
proton, electron and neutron
2. What is the value of the mass number in the isotope
?
131
3. What is the term for atoms of the same element having different masses due to a different
number of neutrons?
isotopes
4. What is the process by which certain isotopes emit particles and release large amounts of
energy?
radioactive decay
5. What do we call electrically charged particles that result from the gain of one or more
electrons by a parent atom?
anions
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Chapter 02 - The Structure of the Atom and the Periodic Table
6. Dalton proposed that all atoms of an element have identical properties. Briefly, explain why
this proposal is invalid.
Isotopes of an element have different properties, particularly their mass.
7. J. J. Thomson in 1897, announced that cathode rays consisted of a stream of _______.
electrons
8. In one sentence, state Rutherford's important contribution to our knowledge of atomic
structure.
He concluded that atoms have a small, heavy, positively charged nucleus surrounded largely
by empty space, occupied by electrons.
9. What instrument is used to study the wavelengths of light emitted and absorbed by atoms?
a spectrophotometer
10. In Bohr's model of the hydrogen atom, what is an "orbit"?
An orbit is a circular path followed by the electron.
11. In Bohr's theory of the atom, what is the number n (n = 1, 2, 3, ...) called?
quantum number
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Chapter 02 - The Structure of the Atom and the Periodic Table
12. In one sentence, explain the meaning/consequences of Heisenberg's Uncertainty
Principle.
It is impossible to know the exact position and momentum of a particle, such as an electron in
an atom.
13. In modern atomic theory, Bohr's orbits are replaced by atomic orbitals. What is an atomic
orbital?
It is a region of space where an electron is likely to be found; or, an electron "cloud".
14. Which two scientists in 1869 arranged the elements in order of increasing atomic masses
to form a precursor of the modern periodic table of elements?
Mendeleev and Meyer
15. Who stated that the elements, when arranged according to their atomic masses, showed a
distinct periodicity of their properties?
Dimitri Mendeleev
16. In the modern periodic table, how are the elements arranged?
by increasing atomic number
17. The modern periodic law states that the physical and chemical properties of the elements
are periodic functions of what property?
atomic number
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Chapter 02 - The Structure of the Atom and the Periodic Table
18. What do we call the horizontal row of elements on the periodic table?
periods
19. How many periods are found on the periodic table?
seven
20. Which period contains the element sodium?
period three
21. What do we call the columns of elements on the periodic table?
groups
22. For an atom, what number gives the number of electrons and protons found in that atom?
atomic number
23. What is the general name given to the elements of Group IA (1)?
alkali metals
24. What term is used for the elements straddling the "staircase" boundary between the metals
and nonmetals?
metalloids
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Chapter 02 - The Structure of the Atom and the Periodic Table
25. For a representative element, how can we deduce the number of valence electrons in a
neutral atom from the position of the element in the periodic table?
the group number is also the number of valence electrons
26. In what way(s) are the three orbitals in the 2p sublevel similar? In what way(s) are they
different?
They have the same shape and the same energy. They are oriented differently in space.
27. What requirement must be met in order for two electrons to coexist in the same orbital?
they must have opposite spins
28. State the Aufbau Principle.
Electrons occupy the available orbital of lowest energy first.
29. Give the electronic configuration in an atom of neon, element number 18.
1s22s22p6
30. Give the electronic arrangement in an atom of strontium, element number 38.
1s22s22p63s23p64s23d104p65s2
31. How many valence electrons are present in a chloride ion?
eight
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Chapter 02 - The Structure of the Atom and the Periodic Table
32. State the Octet Rule.
Elements tend to react in such a way as to attain the electron configuration of the atoms of the
noble gas nearest to them in the periodic table.
33. Give the name of a Group VIIA (17) ion that has the following electronic arrangement:
1s22s22p63s23p6
chloride
34. Give the complete electronic arrangement of a sulfide ion, S2-.
1s22s22p63s23p6
35. Atoms with the biggest radii occur in the _______ _______ region of the periodic table.
bottom left
36. How would you expect an Al3+ ion to compare in size with an Al atom? Explain why.
The ion will be much smaller. In forming the ion, the atom loses all its outermost electrons.
The net positive charge on the ion ensures that all the electrons in the ion are strongly
attracted to the nucleus, keeping the ion small.
37. Which group of elements has the highest ionization energies? Which group has the
lowest?
Group VIIIA (18) are the highest; Group IA (1) are the lowest.
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Chapter 02 - The Structure of the Atom and the Periodic Table
38. Explain what is meant by electron affinity.
It is the energy released when a neutral atom gains an electron to form an anion.
39. _________ is the ion responsible for the regulation of blood pressure and involved in the
transmission of neural impulses.
Ca2+
Multiple Choice Questions
40. What does the mass number minus the atomic number represent?
A. Number of protons
B. Number of electrons
C. Number of neutrons
D. Number of protons - number of neutrons
E. Number of neutrons - number of protons
41. In a neutral atom, what number equals the number of electrons?
A. Atomic number
B. Mass number
C. Mass number minus the atomic number
D. Both A and C
E. None of the above
42. Given that helium has an isotope
atom.
A. 1
B. 2
C. 4
D. 6
E. 0
, predict the number of electrons in a helium
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Chapter 02 - The Structure of the Atom and the Periodic Table
43. How many neutrons are present in an atom of the isotope
A. 3
B. 4
C. 7
D. 10
E. none of the above
?
44. Microwaves, light and X-rays are all forms of ____________.
A. Electricity
B. High energy electrons
C. Electron repulsion
D. Electromagnetic radiation
E. Radioactivity
45. Where are the alkaline earth metals located on the periodic table?
A. IA (1)
B. IIA (2)
C. IIIA (3)
D. VIIA (17)
E. VIIIA (18)
46. How many orbitals are in an s sublevel? How many in a p sublevel?
A. S: 1, p: 2
B. S: 2, p: 3
C. S: 1, p: 3
D. S: 2, p: 6
E. S: 3, p: 3
47. How many electrons are present in an atom of silicon?
A. 14
B. 16
C. 18
D. 24
E. 26
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Chapter 02 - The Structure of the Atom and the Periodic Table
48. Give the name of a Group IA (1) ion that has the following electronic arrangement:
1s22s22p6
A. Lithium ion
B. Sodium ion
C. Potassium ion
D. Magnesium ion
E. Calcium ion
49. What ion carries two negative charges and is isoelectronic with K+?
A. O2B. S2C. F2D. Cl2E. Ar2-
50. What kind(s) of particles can be found outside the nucleus of an atom?
A. Protons
B. Neutrons
C. Electrons
D. Protons and electrons
E. Protons and neutrons
51. The total mass of the protons in any neutral atom is about _______ times the total mass of
electrons in the atom.
A. 0.0005
B. 0.3
C. 1
D. 2
E. 2000
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Chapter 02 - The Structure of the Atom and the Periodic Table
52. What is the quantity represented by the mass number minus the atomic number?
A. Number of atoms
B. Number of neutrons
C. Number of electrons
D. Number of protons
E. Number of particles in the nucleus
53. Which isotope of hydrogen has two neutrons?
A. Hydrogen-1
B. Hydrogen-2
C. Hydrogen-3
D. Deuterium
E. H2
54. Which of the following accounts for the fact that chlorine has an atomic mass of 35.45
amu rather than a whole number?
A. Isotopes
B. Electrons
C. Protons
D. Radioactivity
E. Isomers
55. Who discovered that cathode rays consist of a stream of negative particles, electrons?
A. Crookes
B. Thomson
C. Geiger
D. Rutherford
E. Bohr
56. Who discovered the existence of the atomic nucleus?
A. Crookes
B. Thomson
C. Geiger
D. Rutherford
E. Bohr
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Chapter 02 - The Structure of the Atom and the Periodic Table
57. In Rutherford's experiment, which led to the discovery of the atomic nucleus, what type of
particle or ray was fired at the gold foil target?
A. Alpha
B. Beta
C. Gamma
D. Neutrons
E. Cathode rays
58. In Mendeleev's table of the elements, they were arranged according to ______________.
A. Atomic number
B. Mass number
C. Atomic mass
D. Neutron number
E. Density
59. The modern periodic table is arranged according to what property?
A. Atomic number
B. Mass number
C. Atomic mass
D. Neutron number
E. Density
60. What do we call a complete horizontal row of elements on the periodic table?
A. Group
B. Period
C. Family
D. Representative elements
E. Transition elements
61. What are all the elements in the A-groups often called?
A. Transition elements
B. Lanthanides
C. Metals
D. Non-metals
E. Representative elements
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Chapter 02 - The Structure of the Atom and the Periodic Table
62. Which of the following elements is a metalloid?
A. C
B. Ge
C. Pb
D. N
E. P
63. Where are the halogens located on the periodic table?
A. Representative elements
B. Transition metals
C. Group VIIA (17)
D. Group IIA (2)
E. Group IIIA (3)
64. How many valence electrons are in an atom of carbon?
A. 8
B. 6
C. 4
D. 1
E. 0
65. What is the lowest energy sublevel of a principal level?
A. d
B. e
C. f
D. s
E. p
66. How many sublevels are there in the third principal energy level?
A. 3
B. 2
C. 1
D. 0
E. 4
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Chapter 02 - The Structure of the Atom and the Periodic Table
67. How many orbitals are there in the second principal energy level?
A. 2
B. 3
C. 1
D. 0
E. 4
68. Which of the following correctly gives the electron capacity of a principal energy level in
terms of the number n?
A. n
B. 2n
C. 2n + 2
D. N2
E. 2n2
69. What is the electron configuration of sulfur, atomic number 16?
A. 1s21p62s22p6
B. 1s22s22p62d6
C. 1s22s22p63s23p4
D. 1s22s22p63s23d4
E. 1s22s22p63s22d4
70. Which one of the following electron configurations is appropriate for a normal atom?
A. 1s12s1
B. 1s22s1
C. 1s22s22p8
D. 1s22s22p43s1
E. 1s22s22p63d1
71. Which of the following elements is most likely to form a 2+ ion?
A. Li
B. K
C. Al
D. N
E. Cu
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Chapter 02 - The Structure of the Atom and the Periodic Table
72. Give the complete electronic configuration of a sodium ion.
A. 1s22s22p5
B. 1s22s22p6
C. 1s22s22p63s1
D. 1s22s22p63s2
E. 1s22s22p63s23p64s1
73. Which of the following ions does not follow the octet rule?
A. Na+
B. Ca2+
C. Al3+
D. N3E. Cl2-
74. Which of the following atoms has the biggest size (radius)?
A. Na
B. Al
C. Cl
D. Rb
E. I
75. Which of the following elements has the highest ionization energy?
A. Li
B. B
C. O
D. F
E. He
76. Which of the following elements has the lowest ionization energy?
A. Li
B. B
C. O
D. F
E. Ne
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Chapter 02 - The Structure of the Atom and the Periodic Table
77. The electron affinity is _________________.
A. The energy required to remove an electron from an isolated atom
B. The force between two electrons in the same orbital
C. The force between two ions of opposite charge
D. The energy released when an isolated atom gains an electron
E. The attraction of an atom for an electron in a chemical bond
78. Which one of the following elements has the highest electron affinity?
A. Li
B. K
C. Kr
D. O
E. Cl
79. Which of the following statements relating to Bohr's model of the hydrogen atom is
incorrect?
A. The lowest energy orbit has quantum number n = 1
B. The highest energy orbits are farthest from the nucleus
C. In a transition from the n = 3 to the n = 1 level, light is emitted
D. Energy differences between energy levels can be calculated from the wavelengths of the
light absorbed or emitted
E. The Bohr model consists of energy levels that are evenly spaced, like the rungs of a ladder
80. Who proposed that electrons could behave like waves, as well as like particles?
A. Thomson
B. Rutherford
C. Bohr
D. De Broglie
E. Heisenberg
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Chapter 02 - The Structure of the Atom and the Periodic Table
True / False Questions
81. In the calcium atom represented by the symbol
and 20 electrons.
TRUE
, there are 20 protons, 20 neutrons
82. All atoms of a particular element have identical chemical properties.
TRUE
83. An atom cannot be created, divided, destroyed or converted to any other type of atom.
FALSE
84. The atomic number of an ion tells us the number of protons that are present.
TRUE
85. If an atom gains one electron, it becomes an anion.
TRUE
86. The first experimentally based theory of atomic structure was proposed by John Dalton.
TRUE
87. J. J. Thomson was the first to state that an atom is mostly empty space.
FALSE
88. Short wavelengths of electromagnetic radiation have more energy than long wavelengths.
TRUE
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Chapter 02 - The Structure of the Atom and the Periodic Table
89. Bohr was the first to use the term "orbit" to explain the fixed energy levels of electrons.
TRUE
90. Niels Bohr developed a theory which accounted for the lines in the visible region of the
hydrogen spectrum.
TRUE
91. In Mendeleev's table, the elements were arranged according to their atomic mass.
TRUE
92. There are nine periods on the periodic table.
FALSE
93. Sulfur (S) is one of the representative elements.
TRUE
94. Europium (Eu) is a lanthanide element.
TRUE
95. Arsenic (As) is a metalloid.
TRUE
96. Valence electrons are involved when atoms form bonds.
TRUE
97. There are a maximum of 50 electrons in principal energy level number five.
TRUE
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Chapter 02 - The Structure of the Atom and the Periodic Table
98. Atoms of the noble gas elements, Group VIII A (18), do not form bonds with any other
elements.
FALSE
99. There are eight valence electrons in a chloride ion.
TRUE
100. The ions formed from Group IIA (2) atoms have charges of 2+.
TRUE
101. Cations tend to be formed from metal atoms, while anions are formed from non-metal
atoms.
TRUE
102. The atoms of smallest radius are those of elements in top left hand part of the periodic
table.
FALSE
103. The halogens, Group VII A (17) have the lowest ionization energies of any group in the
periodic table.
FALSE
104. The last period in the periodic table is incomplete.
TRUE
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