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EXAM 3A
Spring 2003

1. Complete and balance the following reactions.

a. aqueous sulfuric acid plus solid strontium hydroxide

b. C5H10NH(aq) + H2O(l)

c. C2H5NH2(aq) + HClO4(aq)

d. Ni(ClO4)2(aq) + NaOH(aq)

e. Pb(C2H3O2)2(s) + HCl(aq)

f. NH3(aq) + HIO3(aq)

g. Mg2+(aq) + H2O(l)


2. Determine if the following salts are acidic, basic, or neutral in aqueous solution. Write out all the pertinent chemical reactions that you need to consider to answer the question.

a. Na2HPO4

b. CoCl2

c. KF


3. A buffer is prepared to be 0.10 M NH3 and 0.10 M NH4Cl.

a. Find the pH of the buffer at 25 oC. Write all of the appropriate chemical reactions, and setup the problem until you are required to do algebra. Choose the pH from one of the following values: 1.00, 4.75, 7.00, 9.25, 13.00. No work = no credit.

b. 0.025 moles of HCl(g) is added to 1.0 L of the buffer. Write any new chemical reactions that occur and estimate the new pH in the buffer solution without doing any calculations.


4. Consider the solubility of silver iodate.

a. Find the molar solubility in water. Write the appropriate chemical reactions and setup the problem until you are required to do algebra. The molar solubility is given by one of the following values: 1.7×10–4, 3.0×10–8, 9.2×10–9, 8.5×10–17. No work = no credit.

b. Find the molar solubility of silver iodate in a 0.10 M solution of sodium iodate.