Review Questions

1. The Mg²⁺ ion has how many electrons?

   1. 12
   2. 10
   3. 14
   4. 24

2. It can be shown using mass spectrometry that the ratio of naturally occurring chlorine-35 to its isotope chlorine-37 is 3:1. Assuming that no other isotopes existed, what would be the atomic weight of chlorine?

   g/mol

3. The maximum number of electrons in a shell with the principal quantum number equal to 4 is

   1. 2
   2. 10
   3. 16
   4. 32

4. If the principal quantum number of a shell is equal to 2, what types of orbitals will be present?

   1. s
   2. s and p
   3. s, p, and d
   4. s, p, d, and f

5. The total number of electrons that could be held in a sublevel with azimuthal quantum number equal to 2 is

   1. 2
   2. 6
   3. 8
   4. 10

6. An element with an atomic number of 26 has how many electrons in the 3d orbital?

   1. 0
   2. 2
   3. 6
   4. 8
   5. 10

7. In going from 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ to 1s² 2s² 2p⁶ 3s² 3p⁵ 4s², an electron would

   1. absorb energy
   2. emit energy
   3. relax to the ground state
   4. bind to another atom
   5. undergo no change in energy

8. Which of the following orbitals has the lowest energy?

   1. 2p
   2. 3s
   3. 3d
   4. 4s
   5. 3p

9. Which of the following correctly represents an excited state of scandium?

   1. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s²
   2. 1s² 2s³ 2p⁵ 3s² 3p⁶ 3d¹ 4s²
   3. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d² 4s¹
   4. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d² 4s²
   5. 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹ 4s⁰