Arkansas State University 
Department of Chemistry
and Physics
CHEM2004
Exam 3

 
CHEM2004 Name_______________________
Exam 3 Fall 2002

1. Describe the effect on pH when each of the following are placed in water:   (6 points)

 a)  oxides of a nonacidic cation -
 b)  oxides of a weakly acidic cation -
 c) covalent oxides -

2. Predict the product(s) for the following reaction:  Label the acidic oxide, the basic oxide and balance the equation.     (18 points)

  N2O5       +      OsO4   ------->

  SeO2         +      CrO      ------->

  P2O3         +      H2O       ------->

  Cr2O3         +      H2O      ------->
  (Cr+3 is a moderately acidic cation)

  Cr2O3         +      H+      ------->

  FeO          +      CO2      ------->

3. Determine the C.N.(+), C.N.(-) and lattice type for: (9 points)
 
C.N.(+)
C.N.(-) 
lattice type
B2O3      
RbF         
Tl2O       
B 41; F 119; O 126; Tl 164; Rb 166 pm

4. Describe how CO is produced industrially.   (4 points)

5. Why is it difficult to prepare pure oxoacids?   (4 points)

6. Why should you be careful when using P4O10 as a drying agent for organic solvents?(4 points)

7. Describe how sulfuric acid is prepared starting from sulfide ores. (8 points)

8. What are the characteristic acid and base for water?   (4 points)

9. What is meant by the terms bridging and terminal oxides?  (4 points)

10. Why does CO burn yet CO2 is used as a fire extinguisher?  (6 points)

11. Fill in the blank with the appropriate oxide or oxoacid. (2 points each)

Fischer-Tropsch reaction  _______________________________

Syn-gas   ________________________________________

Photosynthesis  __________________________________

Used as a fire extinguisher  ___________________________

Number one chemical produced in tons per year  _________________________

Greenhouse gas  _________________________________

Oxoacid used to make ammonium nitrate __________________________

12. List the three environmental concerns associated with NOx’s.  (6 points)

13. List the three nonmetal oxides that have no effect on pH in aqueous solutions (3 points)

14. Define a disproportionation reaction.  Explain why NO2 undergoes disproportionation.  (4 points)

15.  Using NaOH and Na2O, explain the leveling effect.  (6 points)