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Exam 2B
Spring 2005

March 11, 2005


Possibly useful information:

pH = –log[ H3O+ ]

 

pOH = –log[ OH ]

pH + pOH = 14.00 at 25 oC

 

 

log(1.0×10–3) = –3

 

log(1.0×10–4) = –4

log(2.0×10–3) = –2.698970004

 

log(2.0×10–4) = –3.696870004

log(3.0×10–3) = –2.522878745

 

log(3.0×10–4) = –3.522878745

log(4.0×10–3) = –2.397940009

 

log(4.0×10–4) = –3.397940009

log(5.0×10–3) = –2.301029996

 

log(5.0×10–4) = –3.301029996

log(6.0×10–3) = –2.22184875

 

log(6.0×10–4) = –3.22184875

log(7.0×10–3) = –2.15490196

 

log(7.0×10–4) = –3.15490196

log(8.0×10–3) = –2.096910013

 

log(8.0×10–4) = –3.096910013

log(9.0×10–3) = –2.045757491

 

log(9.0×10–4) = –3.045757491


1. Complete and balance the following reactions:

a. H3PO4(aq) + CsOH(aq)

b. C6H5NH2(aq) + HBr(aq)

c. HClO2(aq) + H2O(l)

d. Ba(OH)2(s) + HClO4(aq)

2. Complete and balance the following reaction and identify the acid, the base, the conjugate acid, and the conjugate base:

bicarbonate ion + cyanide ion

3. Identify the Lewis acid and the Lewis base in the following reaction.

Cd2+(aq) + 4 NH3(aq) [Cd(NH3)4]2+(aq)

4. Identify the stronger acid in pair given below. Briefly (5 words or less) justify your reasoning.

a. H2Se or H2Te

b. H2SO3 or H2SeO3

5. Calculate the pH and pOH of the following solutions:

a. 2.0×10–4 M hydrobromic acid.

b. 3.0×10–4 M lithium hydroxide.

c. 4.0×10–4 M calcium hydroxide.

6. Consider the reaction shown below, which has H = 131 kJ/mol.

C(s) + H2O(g) CO(g) + H2(g)

a. Which way will the reaction shift if graphite(solid carbon) is added to the reaction? Explain.

b. Which way will the reaction shift if the temperature is raised? Explain.

7. Estimate the pH of a 1.0×10–2 M solution of phenol, C6H5OH. Show all the steps needed to solve the problem until you are required to do algebra. Then make a chemically reasonable estimate of the pH. Ka = 1.0×10–10