LECTURE QUESTIONS ON ATOMIC STRUCTURE, CHEMICAL SYMBOLS, ATOMIC NUMBER, MASS
NUMBER, ISOTOPES, AVERAGE ATOMIC MASS
Part 1: Element Names
1. What is the correct way to write a chemical symbol?
2. Why do some of the symbols not match the name of the element?
Make sure you can recognize the chemical symbols for following elements
Name
Hydrogen
Helium
Lithium
Beryllium
Boron
Carbon
Nitrogen
Oxygen
Fluorine
Neon
Sodium
Magnesium
Aluminum
Silicon
Phosphorus
Sulfur
Name
Chlorine
Argon
Potassium
Calcium
Iron
Nickel
Copper
Zinc
Bromine
Silver
Tin
Iodine
Gold
Mercury
Lead
Uranium
Symbol
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Part II: Atomic Structure and Model
1. When was the concept of an atom first made?
2. What does atom mean?
3. How can electrons move from one energy level to another?
4. Summarize Dalton’s atomic theory in your own words.
5. Summarize Bohr’s Model
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Symbol
Cl
Ar
K
Ca
Fe
Ni
Cu
Zn
Br
Ag
Sn
I
Au
Hg
Pb
U
6. How can we study what we can’t even see?
7. How did Rutherford discover the nucleus?
8. What two subatomic particles are in the nucleus?
9. Write down each subatomic particle, its symbol, charge, and mass number.
10. Summarize the quantum mechanical model.
11. Define an orbital.
12. What is the speed at which electrons travel?
13. What percent of the time can we locate where an electron is?
Part III: Mass Number and Isotopes
1. What is the unit to measure the mass of atoms?
2. 1 atomic mass unit = _______________ grams
3. What does the atomic number tell you about an element or atom?
4. Are elements named according to the number of protons, neutrons, or electrons?
5. If the atomic number of an atom changes then the atom is or is not a different element?
6. Define isotope.
7. Give the formula for mass number
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8. What is the difference between mass number and average atomic mass?
9. Which type of mass is shown on the periodic table?
10. What are some positive uses of isotopes?
Part IV: Practice Problems
1) Complete the table:
Chemical symbol
Mass number
Number of protons
3
4
6
Number of electrons
Number of neutrons
2
9
1
10
18
2) The mass number of an unidentified element is 10. The element has five neutrons. What is this element?
3) Carbon has three isotopes. One has 6 neutrons, one has 7 neutrons, and one has 8. Draw their symbols below:
4) Write the symbol for the isotope. Use both ways to write the symbols for isotopes.
a. with 8 protons and 8 neutrons
c. with 16 protons and 17 neutrons
b. with 28 protons and 30 neutrons
d. with 92 protons and 146 neutrons
5) Complete the following table:
Element
Calcium (Ca)
Nickel (Ni)
Gold (Au)
Atomic
Number
79
6
Number of
Protons
Number of
Neutrons
20
28
20
Mass
Number
59
118
14
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Isotope
Symbol
6) Complete the following table.
7) Challenge Problem: Copper has two naturally occurring isotopes: copper-63 and copper-65. The relative
abundance of copper-63 is 69.17%; the atomic mass of copper is 62.94 amu. The relative abundance of copper65 is 30.83%; its atomic mass is 64.93 amu. Determine the average atomic mass for copper. How close is your
answer to the value shown on the periodic table?
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