Unit 3 – Practice Problems
Dalton Atomic Theory:
1.
2.
3.
4.
5.
Thompson Model of the Atom:
Aka:
pudding model
Rutherford Model of the Atom:
At the center of the atom is the
The negatively charged
which contains the
are distributed around the
.
.
Bohr Model of the Atom:
Aka: The ________________ model
Bohr discovered that electrons exist in ___energy_________ levels which later led to the
discovery of energy ______________.
Subatomic Particles
Particle
Symbol
Location
Relative Charge
Relative Mass
Atomic Notation
1.
3.
2.
Example:
12
C
6
Element
Atomic Number
Number of Protons
Atomic Mass
Number of Neutrons
Element
Symbol
Atomic
Atomic
Number of
Number of
Number
Mass
Protons
Neutrons
N
15
Strontium
84
78
118
186
74
Isotopes
Definition:
Simple and Weighted Averages
Simple:
Weighted:
Not all isotopes of an atom are present in equal proportions, so
calculate average atomic mass.
Example:
Bromine has 2 stable isotopes:
1.
79
2.
81
Br has a mass of 78.919 amu and 50.69% abundance
Br has a mass of 80.916 amu and 49.31% abundance
The average mass of Br is:
Orbital Filling
Define Aufbau Principle:
Hund’s Rule:
average is used to
Draw an orbital filling diagram for:
Be
F
V
Quantum Numbers
Define the 4 different quantum numbers. What do they represent
Identify 4 plausible quantum numbers for each of the following atoms. (Quantum numbers refer
to the final electron unless otherwise stated. For example: Ne has 10 electrons, what are the
quantum numbers for the 10th electron).
Practice Problems
1) What is the term for a symbolic method of expressing the composition of an atomic
nucleus?
A) atomic notation
B) atomic number
C) atomic mass
D) mass number
E) none of the above
4) Which of the following subatomic particles are found inside the nucleus?
A) electron and neutron
B) neutron and proton
C) proton and electron
D) all of the above
E) none of the above
5) Using atomic notation, indicate the isotope having 26 p+, 32 n0, and 26 e-.
A) Fe
B)
Fe
D)
S
E)
S
6) How many neutrons are in the nucleus of an atom of
Co?
A) 33
B) 27
C) 60
D) 87
E) none of the above
7) Element W has two natural isotopes: W-10 (10.013 amu) and W-11 (11.009 amu).
Calculate the atomic mass of element W given the abundance of W-10 is 19.66%.
A) 4.133 amu
B) 10.21 amu
C) 10.51 amu
D) 10.81 amu
E) 16.89 amu
8) Element Y has two natural isotopes: Y-63 (62.940 amu) and Y-65 (64.928 amu).
Calculate the atomic mass of element Y given the abundance of Y-63 is 69.17%.
A) 63.55 amu
B) 64.00 amu
C) 64.32 amu
D) 107.85 amu
E) 108.46 amu
9) How many unpaired electrons does Rh have?
A) 1
B) 2
C) 3
D) 4
E) 5
10) What is the angular momentum quantum number (l) for Ge?
A) 0
B) 1
C) 2
D) 3
11) How many possible magnetic quantum numbers could U have?
A) 1
B) 3
C) 5
D) 7