Arkansas State University  Department of Chemistry and Physics
CHEM2004	Exam 2b

CHEM2004                                                                                                                                 Name_________________________

Exam 2b                                                                                                                                       Fall 2006

1.         List the categories of acidity.                                 (6 points)

2.         Which would have the higher DH_hyd, NaCl or CaCl₂?  Briefly explain why.  (Both have approximately the same size ions and are close in electronegativities)           (4 points)

3.         Explain how electronegativity affects the amount of hydrolysis.  (4 points)

4.         Label each of the following as either a hydrated ion, hydroxycation, insoluble hydroxide, oxoanion, hydroxyanion, insoluble metal oxide or oxoacid. (8 points)

       a) Fe₃O₄

b) Ca(OH₂)₅ (OH)⁺

c) P(H₂O)₄^3-

d) Cr(OH)₃

e)  SO₄^{2 -}

f)  SiO₂(OH)₂^{2 -}

g)  Al(OH₂)₆ ^{3 +}

h)  H₂CO₃  or CO(OH)₂

5.         for the ions below, tell which will be colored and which have no color to their solution.                                                     (4 points)

Cu^{+ 2}

Mg^{+ 2}

S ^{- 2}

Cr ^{+ 3}

6.         Determine the oxoanion for each of the following ions.      (10 points)

a)   Cl ^{+ 5}

b)  P ^{+ 3}

c)  Si ^{+ 4}

d)  N ^{+ 3}

e)  Mo ^{+ 6}

7.         Do you expect SnO₆^{8 –}  to exist in water?  Justify your answer.  (4 points)

8.                  Write the net ionic equation for Fe₃(PO₄)_{2 (s)}.  (6 points)

9.         Explain why IO^- is a better base than IO₄^-.   (4 points)