CHM 1025C Module 5i Part E1 Sample Test Answers
Module 5i E1: Classification of Chemical Reactions Sample       10 Points

(Sections 7.4)

Classify Each of the following (unbalanced) chemical reactions as:

  1. Combination (or synthesis)
  2. Decomposition (or Anaylsis)
  3. Single Replacement
  4. Double Replacement (Precipitation)
  5. Double Replacement (Neutralization)
  6. Double Replacement (Gas Forming)
  7. Combustion of a hydrocarbon

 

___A___1.            Fe     +      FeCl3       --->       FeCl2

 

__E__2.                  HCl         +        Mg(OH)2   --->     MgCl2      +      HOH

 

___C__3.             Mg        +      HNO3    --->   Mg(NO3)2      +   H2

 

___A__4.             H2  +   N2   --->   NH3

 

__F__5.           NaHCO3   + HCl     --->    NaCl   +   CO2    +  H2O

 

__D__6.            Ca(NO3)2  +  K3PO4  ---> Ca3(PO4)2  +  KNO3

 

__B__7.             KClO3   --->   KCl  +    O2

 

__C__8.             Na  +  H2O   --->  NaOH  +  H2

 

(See Questions #21-24  p215 for more practice)

Writing Chemical Reactions (Section 7.2)

 

9. Write a chemical equation for solid cadmium(II) hydrogen carbonate decomposing to yield solid cadmium(II) carbonate, water, and carbon dioxide gas:

 

Cd(HCO3)2 (s)    --->     CdCO3 (s)     +    H2O (l)   + CO2  (g)

 

10. Write a chemical equation for the reaction of aqueous solutions of potassium chromate and calcium sulfate to give the precipitate calcium chromate and aqueous potassium sulfate.

 

K2CrO4  (aq)  +  CaSO4 (aq)  --->   CaCrO4  (s)   +  K2SO4 (aq)

 

See additional question #7-17 p215