(6 pts.) 1. Write the electron configuration beyond a noble gas core (for example, F, [He]2s², 2p⁶) for an atom of Ni.

[Ar]4s²3d⁸

(3 pts.) 2. What is the spectroscopic notation for an atom in an energy state in which L = 3 and S = 2.

L^2S+1 leads to F⁵

(6 pts.) 3. Describe and explain the trends in the periodic table for the atomic radius.

The atomic radius decreases left to right across a period and increases top to bottom down a family. Going across a period, the effective atomic number increases as the electrons are added as individual charges whereas the nucleus acts as point charge. This causes the electrons to be attracted closer to the nucleus. Going down a column the outer electrons are shielded from some of the nuclear charge by the inner electrons resulting in the electrons being less tightly held.

(9 pts.) 4. Draw the three Lewis electron dot resonance structures for [NO₃ ]^-1.

5. For the following compound

(3 pts.) Draw the Lewis electron dot structure.

(3 pts.) Using the VSEPR Theory, predict the shape of the molecule (specify the number of bond and lone pairs of electrons).

4 bond pairs; 1 lone pair; See Saw shape

(2 pts.) Specify the type of hybridization present.

dsp³

(2 pts.) Using your molecular models, determine the principal axis of rotation.

C₂

(2 pts.) Determine if there are any non-coincident axes of rotation.

No

(2 pts.) Determine which type of mirrors, if any are present.

vertical mirrors

(2 pts.) Specify the point group for the molecule.

 C_2v

6. For the following ion

(3 pts.) Draw the Lewis electron dot structure.

(3 pts.) Using the VSEPR Theory, predict the shape of the molecule (specify the number of bond and lone pairs of electrons).

4 bond pairs; 2 lone pairs; square planar

(2 pts.) Specify the type of hybridization present.

d²sp³

(2 pts.) Using your molecular models, determine the principal axis of rotation.

C₄

(2 pts.) Determine if there are any non-coincident axes of rotation.

yes; 4

(2 pts.) Determine which type of mirrors, if any are present.

both horizontal and vertical mirrors

(2 pts.) Specify the point group for the molecule.

 D_4h

(3 pts.) 7. Complete the following nuclear reaction.

2 ¹²C ---> ²⁰Ne + ⁴He

(4 pts.) 8. For the 3d³ electron configuration, specify the principal and secondary quantum numbers and possible values for the magnetic and spin quantum numbers.

n = 3; l = 2; m_l values +2, +1, 0, -1, or -2; s = +1/2 or -1/2

(6 pts.) 9. Using Slater’s rules, calculate the effective nuclear charge for a 3d electron in Ni.

₂₈Ni

z^* = z - s = 28 - (20 - 7(0.35)) = 5.55

(6 pts.) 10. Describe and explain the trend in radius for the iso-electronic series involving S^-2 through Ca⁺².

An isoelectronic series is a series of negative ions, a noble gas, and positive ions that have the same number of electrons and electronic configuration. As the positive charge increases form S^-2 through Ca⁺² the size decreases due to the increasing point charge on the nucleus.

(2 pts.) 11. Give an example of orbitals (atomic and/or hybridization) that can be combined to form a sigma bond.

s-s, p-p, s-p, and all combinations of atomic and hybrid orbitals.

(2 pts.) 12. Give an example of atomic orbitals that can be combined to form a pi bond.

 p_x-p_x, p_y-p_y, p_x-d_xz, p_y-d_yz, etc.

13. For the following compound

(3 pts.) Draw the Lewis electron dot structure.

(3 pts.) Using the VSEPR Theory, predict the shape of the molecule (specify the number of bond and lone pairs of electrons).

2 bond pairs; 1 lone pair; bent

(2 pts.) Specify the type of hybridization present.

sp³

(6 pts.) 14. For PF₅, give the energy diagram for ground state P atom, hybrid state P atom without F atoms, and hybrid state P atom showing electrons contributed by F atoms.

(15 pts.) 15. Derive the spectral terms for the p⁴ configuration. Show all the micro-states. Identify the ground-state term. Give all J values for the ground-state term and indicate which is lowest in energy.