L. Farrell – Chemistry 11 – Atomic The ory Review – Answers - Page 1 of 7
Atomic Theory Review
Fill in the Blank
mass number
1. The number of protons and neutrons in the nucleus of an atom is the __.
isotopes
2. Atoms possessing the same number of protons but a different number of neutrons are __.
ground state
3. The lowest energy state of an electron in an atom is the __.
nucleon
4. A particle found in the nucleus is called a(n) __.
atomic number
5. The number of protons in an atom is represented by the __.
protons
6. The identity of an element is determined by the number of __ present.
orbital
7. The volume and shape of the region in space where you would be most likely to locate an electron is a(n) __.
diagonal rule
8. A system for predicting the order of filling energy sublevels with electrons is the __.
orbital
9. The letters s, p, d, or f, are used to designate a particular __ within an energy level.
Multiple Choice
D
1. Of the following assumptions or results of Dalton’s
atomic theory, the only one that remains essentially
correct in most cases is
A) All atoms of an element are identical in mass.
B) Atoms are indivisible and indestructible.
C) Oxygen has an atomic weight of 7.
D) Atoms of elements combine in the ratios of small
whole numbers to form compounds.
A
2. Rutherford’s experiments on the scattering of
particles by thin metal foils established that
A) The mass and charge of an atom are concentrated
in a nucleus.
B) Electrons are fundamental particles of all matter.
C) All electrons have the same charge.
D) Atoms are electrically neutral.
C
3. The species that has the same number of electrons as
32
16
S is
A)
35
17
Cl
-
B)
34
16
S
+
C)
40
18
Ar
2+
D)
35
16
S
2-
C
4. All of the following masses are possible for an individual
carbon atom except one. That impossible one is
A) 12.000 00 amu C) 12.011 15 amu
B) 13.003 35 amu D) 14.003 24 amu
D
5. There are two principal isotopes of indium (atomic
weight = 114.82). One of these,
113
49
In, has an atomic mass
of 112.9043 amu. The second isotope is most likely to be
A)
111
49
In B)
112
49
In C)
114
49
In D)
115
49
In
Short Answer
1. Compare the similarities and differences between Rutherford’s and Bohr’s theories of the atom.
Both Rutherford’s and Bohr’s models of the atom have a nucleus, which is an
extremely small, dense region in the center of the atom, that contains most of
the atom’s mass and all of its positive charge. Both models have negatively
charged electrons orbiting the nucleus. The difference is that Bohr’s model
specifies the exact path of the electrons. According to Bohr, electrons travel in
energy levels. The energy of the electron is quantized – the electron can only
exist at specific allowable energy levels. Rutherford’s model did not specify the
path taken by the electron.
