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The spinels have a general formula AIIB2IIIO4.  The oxide anions form a ccp (fcc) lattice and the cations occupy the tetrahedral or octahedral holes.  For NiFe2O4, please answer to the following questions (Please write your answer on a paper and upload the image file in the Assignments) : (a) Determine the CFSEs of Ni2+ occupying the tetraheral and octahedral holes in terms of Δo.  You must draw the electron configurations in the energy level diagrams (Note: The oxides are weak-field (high-spin) ligands and Δt ~ (1/2) Δo).      (b) Determine the CFSEs of Fe3+ occupying the tetraheral and octahedral holes in terms of Δo.  You must draw the electron configurations in the energy level diagrams (Note: The oxides are weak-field (high-spin) ligands and Δt ~ (1/2) Δo).      (c) Which cation (Ni2+, Fe3+) prefers the octahedral holes more strongly?  Briefly explain your answer. (d) Would you expect NiFe2O4 to form a normal or inverse spinel?  Briefly explain your answer.

An ionic compound forms a cubic-type lattice where A ions occupy the corners of the cube and B ions occupy the centers of faces of the cube.  What is the molecular formula of the compound?   

The radii of Mg2+ and S2- are 0.86 and 1.70 Å, respectively.  Therefore, the radius ratio of MgS is   _______ , which indicate that the maximum coordination number for the magnesium cation should be _______ .  If MgS assumes a rock-salt structure (NaCl), the S2- will form a _______ lattice and Mg2+ will occupy  _______ holes.

The following pairs show coordination compounds and their predicted magnetic properties.  Which pair is correct (There may be more than one answer)?  

Name the following compound. (NH4)2[Ni(C2O4)2(H2O)2]

Please select all correct statements for the following reactions (there may be more than one answer): reaction (1)    [Ni(H2O)6]2+  +  6 NH3  →  [Ni(NH3)6]2+  +  6 H2O    reaction (2)    [Ni(H2O)6]2+  +  3 en  →  [Ni(en)3]2+  +  6 H2O

Which one of the following complexes can exhibit geometrical isomerism?

Dr. Gowen decides to conduct the above study and see if spending time on TikTok decreases students’ overall grades. From her general psychology class, she records students’ overall grades. Then, she assigns students to two groups. Group 1 will watch TikTok videos every day for 30 minutes; Group 2 will not watch TikTok videos at all. The study will continue for 1 month. At the end, she will again record students’ overall grades. In the above study, what is the independent variable?

Match the 4 lobes of the brain with their functions.

When Kyla earns an A on an exam, her parents reward her by giving her $20. Consequently, Kyla is very motivated to score well on her exams. The financial benefit of doing well on exams is providing: