# 2.1 Day 1 Prelab

Questions

1. Describe briefly the Crystal Field Theory.

2. What is a Coordination Compound?

3. Describe some properties of $$[Co(NH_3)_4(CO_3)]NO_3$$ and its structure

4. Write down the reaction that you are going to do in the lab.

5. What is the crystal field stabilization energy?

6. Calculate the crystal field stabilization energy for a tetrahedral cobalt(II) complex. Cobalt(II) is a d7 ion. HINT: There is no low-spin tetrahedral $$(ML_4)$$ complex.

EXTRA

7. Cyanide solution (12.73 mL) was treated with 25.00 mL of $$Ni^{2+}$$ solution (containing excess $$Ni^{2+}$$) to convert the cyanide into tetracyanonickelate(II):

$4 C N^{-}+N i^{2+} \rightarrow N i(C N)_{4}^{2-} \nonumber$

Excess $$Ni^{2+}$$ was then titrated with 10.15 ml of 0.01307 M EDTA. $$Ni(CN)_{4}^{2-}$$ does not react with EDTA. If 39.95 mL of EDTA were required to react with 30.10 mL of the original $$Ni^{2+}$$ solution, calculate the molarity of $$CN^-$$ in the 12.73 mL sample.

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5.35 / 5.35U Introduction to Experimental Chemistry
Fall 2012