Download The Atom Review Packet

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The Atom Review Packet
1. What is the total number of electrons present in an atom of 56Co?
(1) 27
(2) 32
(3) 59
(4) 86
2. A particle of matter contains 6 protons, 7 neutrons and 6 electrons. This particle
must be a
(1) neutral carbon atom
(2) neutral nitrogen atom
(3) positively charged carbon ion
(4) positively charged nitrogen ion
3. What is the mass number of an atom that contains 28 protons, 28 electrons, and
34 neutrons?
(1) 26
(2) 56
(3) 62
(4) 90
4. Neutral atoms of 35Cl and 37Cl differ with respect to their number of
(1) electrons
(2) protons
(3) neutrons
(4) positrons
5. An element has an atomic number of 18. What is the principal energy level of its
outermost electrons?
(1) 1
(2) 2
(3) 3
(4) 4
6. Which is the electron dot structure of an atom of boron in the ground state?
(1)
(2)
(3)
(4)
7. The total number of electrons in a neutral atom of every element is always equal to
the atom’s
(1) mass number
(2) number of neutrons
(3) number of protons
(4) number of nucleons
8. The atomic number of an atom is equal to the number of
(1) neutrons in the atom
(2) protons in the atom
(3) neutrons plus protons in the atom
(4) protons plus electrons in the atom
9. Compared to the entire atom, the nucleus of the atom is
(1) smaller and contains most of the atom’s mass
(2) smaller and contains little of the atom’s mass
(3) larger and contains most of the atom’s mass
(4) larger and contains little of the atom’s mass
10. An atom of carbon-14 contains
(1) 8 protons, 6 neutrons, and 6 electrons (2) 6 protons, 6 neutrons, and 8 electrons
(3) 6 protons, 8 neutrons, 8 electrons
(4) 6 protons, 8 neutrons, 6 electrons
11. The atomic mass of an element is defined as the weighted average mass of that
element’s
(1) most abundant isotope
(2) least abundant isotope
(3) naturally occurring isotopes
(4) radioactive isotopes
12. Which symbols represent atoms that are isotopes of each other?
(1) 14C and 14N
(2) 16O and 18O
131
131
(3) I and I
(4) 222Rn and 222Ra
13. An atom contains a total of 29 electrons. When the atom is in the ground state, how
many different energy levels will contain electrons?
(1) 1
(2) 2
(3) 3
(4) 4
14. In an atom that has an electron configuration of 2 – 7, what is the total number of
electrons in its principal energy level of highest energy?
(1) 2
(2) 5
(3) 6
(4) 7
15. What is the total number of occupied principal energy levels in a sodium atom?
(1) 1
(2) 2
(3) 3
(4) 4
16. An atom with the electron configuration 2 – 8 – 11 – 2 has an incomplete
(1) first principal energy level
(2) second principal energy level
(3) third principal energy level
(4) fourth principal energy level
17. Which is the electron configuration of an atom in the excited state?
(1) 2 – 4
(2) 2 – 3
(3) 2 – 7 – 2
(4) 2 – 8 – 1
18. Which is an electron configuration of a fluorine atom in the excited state?
(1) 2 – 6
(2) 2 – 7
(3) 2 – 6 – 1
(4) 2 – 7 – 1
19. Energy is released when an electron changes from a principal energy level of
(1) 1 to 2
(2) 2 to 3
(3) 3 to 2
(4) 3 to 5
20. The characteristic bright line spectrum of sodium is produced when its electrons
(1) return to lower energy levels
(2) jump to higher energy levels
(3) are lost by the neutral atoms
(4) are gained by the neutral atoms
Part 2 Questions
1. Compare and contrast the mass and charge of a proton, neutron, and electron.
2. What is an isotope? How would you calculate the atomic mass of an isotope? How is an
isotope different from an ion?
3. Determine the number of electrons in the following ions:
a) Li+
b) O2-
c) Al3+
d) Ca2+
4. Write the electron configuration and Lewis dot structure for He, C, F, N, and Ar.
5. Describe Rutherford’s Gold Foil Experiment. What did he conclude from this?
6. What is the difference between ground state and excited state?
7. How is the bright line spectrum formed?
8. Draw Bohr models for the following:
a) oxygen atom
b) oxygen ion
c) magnesium atom
d) magnesium ion
Answer Key
1.
2.
3.
4.
5.
1
1
3
3
3
6. 4
7. 3
8. 2
9. 1
10. 4
11.
12.
13.
14.
15.
3
2
4
4
3
16.
17.
18.
19.
20.
3
3
3
3
1
Part 2
1. (Table O)
Mass
1 amu
1 amu
0 amu
Proton
Neutron
Electron
Charge
+1
0
-1
2. Isotopes: atoms of the same element (same atomic #) that have different numbers of
neutrons (different mass #).
Atomic mass = 1st % (1st mass) + 2nd % (2nd mass) + …
100
Isotopes have different numbers of neutrons (mass # changes, no charge), ions have
different numbers of electrons (mass # stays the same, have a charge)
3.
a) 2
4. Helium: 2
Carbon: 2-4
Fluorine: 2-7
b) 10
c) 10
Nitrogen: 2-5
Argon: 2-8-8
d) 18
5. Rutherford aimed positive alpha particles at gold foil and observed their path. Most of
the alpha particles passed straight through, some were slightly deflected, and some
bounced back. From this, Rutherford concluded that the atom was mostly empty space,
the nucleus has a positive charge, and the nucleus contains most of the atom’s mass
(dense). The electrons are found outside of the nucleus.
6. Ground state is when electrons occupy the lowest energy levels available (closest to the
nucleus). The excited state occurs when electrons absorb energy and move to a higher
energy level, leaving a lower energy level incomplete. Ground state configurations are
found on the Periodic Table, excited state configurations are not.
7. The bright line spectrum is formed when an electron in a higher energy level (excited
state) returns to lower energy levels (ground state) and releases energy in the form of
light/color.
8. a) oxygen atom
8p
8n
b) oxygen ion
2e
-
6e
8p
-
8n
c) magnesium atom
12 p
12 n
2e-
8e-
2e-
8e-
d) magnesium ion
2e-
8e-
2e-
12 p
12 n