Electron worksheet #2
1. A lithium atom has an atomic number of 3 and a mass of 7 a.m.u. The number of
electrons which it has in the second energy level is
1) 1
2) 2
3) 3
4) 4
5) 5
2. The electron dot arrangement around an atom of sulfur is
1) four single dots
2) four pairs of dots
3) two single dots
4) three pair of dots
5) two single and two pair of dots
3. If “n” represents the number of the principle energy level, what is the most electrons that
any level can contain?
1) n
2) 2n
3) n2
4) 2n2
4. A green color is obtained in the flame test for a barium salt. The energy producing this
color is emitted when
1) oxidation takes place
2) electrons are raised to higher energy levels by the heat of the flame
3) electrons drop back to lower energy levels
4) electrons in the highest levels are expelled
5. If “n” represents the number of any principle energy level, how many orbitals are in that
energy level?
1) n
2) 2n
3) n2
4) 2n2
6. The total number of electrons that can fill the “p” sublevel is
1) 3
2) 10
3) 6
4) 8
5) 14
7. The number of orbital pairs of electrons in an atom with an electron configuration of
1s2 2s22p4 is
1) 1
2) 2
3) 3
4) 4
5) 5
8. An orbital may never be
1) unoccupied
2) occupied by one electron
3) occupied by two electrons
4) occupied by more than two electrons;
5) as large as the shell itself.
9. The number of electrons in the highest energy level of the argon atom
(atomic number is 18) is
l) l0
2) 2
3) 6
4) 8
5) none of these.
10. The electron configuration of scandium is ls22s22p63s23p64s23dl . This shows that
1) the 4s electrons are at a lower energy level than the 3d electrons
2) the common oxidation number of scandium is +1
3) three d orbitals are present
4) a new electron shell begins with the d orbital.
11. The highest energy level in an atom is the level that
l) is closest to the nucleus
2) is farthest from the nucleus
3) has the most electrons
4) has only “f” orbitals
12. Fluorine has an atomic number of 9 and an atomic mass of 19.
The number of electrons in the second energy level in this atom is
l) 7
2) 2
3) 9
4) 10
5) 12
13. What is the total number of principle energy levels that are completely filled in an atom
of calcium in the ground state? Note: 20Ca
l) l
2) 2
3) 3
4) 4
5) 5
14. How many orbitals are completely filled in an atom of phosphorus in the ground state?
1) 6
2) 9
3) 12
4) 15
5) none of these
15. The number of orbitals allowed in the second principle energy level of an atom is
1) 1
2) 2
3) 3
4) 4
5) 5
16. What neutral atom has the electron configuration ls2 2s22p6 3s2 3p6 4s1 ?
1) 11Na
2)19K
3) 20Ca
4) 56Ba
5) 17Cl
17. The maximum number of 3rd principle energy level orbitals allowed is
1) 5
2) 7
3) 9
4) 4
5) none of these
18. What is the maximum number of electrons allowed in an orbital?
1) one
2) two
3) three
4) six
5) ten
19. The maximum number of “f” orbitals is
1) 1
2) 3
3) 5
4) 7
5) 10
20. What is the maximum number of electrons that can occupy the 3s orbital?
1) 1
2) 2
3) 3
4) 6
5) 8
21. The maximum number of electrons in the second principle energy level is
1) 1
2) 2
3) 4
4) 6
5) 8
22. In a dot diagram, the chemical symbol at the center of the diagram represents the
1) nucleus of the atom
3) kernel of the atom
2) valence electrons
4) inner electrons of the atom
23. The atom whose outermost principle energy level electrons arrangement most closely
resembles that of oxygen (at. no. 8) has the atomic number
1) 6
2) 10
3) 14
4) 16
24. The valence electrons of the atoms are the electrons found in the
1) kernel
2) nucleus
3)outermost s and p sublevels
4) incomplete inner shell
25. Chlorine may be represented by the electron-dot symbol representing one single
dot and three pairs of electrons. The atom which would be represented by an
identical electron-dot arrangement has an atomic number of
1) 7
2) 9
3) 15
4) 19
26. Electron-dot symbols consist of the symbol representing the element and an
arrangement of dots which show the
1) atomic number
2) atomic mass
3) number of neutrons
4) electrons in the outermost energy level