Ch. 7, 8, 18  chemical equations & reactions  test         [50 points]                    Chemistry

Academic Honesty:   The answers on this test are my own and I am using only the allowed set of notes as described in the syllabus.  I have not discussed the test questions with anyone before or during the test nor have I seen the test questions prior to the exam.  If you violate any of the preceding items or do not sign, your semester grade is a F.

                                                                        Signature:  ___________________

 

1.  Balance the following chemical reactions using the lowest ratio of whole numbers; if the coefficient is “1”, enter it; otherwise, it will be marked as an error.  [10 points]

a.  ___  C2 H6   +  ___  O2   -->  ____  CO2   +  ____  H2 O

b.  ___  Ca(NO3 )2   +  ___  Na3 PO4   -->  ___  Ca3 (PO4 )2   +  ____  NaNO3

 

2.  Write the chemical equation, where zinc metal reacts with hydrogen chloride to form hydrogen gas and zinc chloride; need not balance the chemical equation, but need the correct chemical formulas.  [5 points]

 

3.  What is the oxidation number of __.  [6 points]

a.  Mn in KMnO4

b.  carbon in C2 H6

c.  sulfur in SO4 2-


4.  Write the net ionic equation for __; need not balance the chemical equation, but need the correct chemical formula.   [9 points]

a.  the combustion of methane (CH4 )

b.  mixing aqueous solutions of silver nitrate and potassium chloride

c.    mixing aqueous solutions of sodium carbonate and iron (II) chloride

 

5.  Fill-in the blank with the appropriate letter(s) to identify the type of chemical reaction, i.e. some reactions may have more than a single letter.   [10 points]

a.  double replacement reaction
b.  single replacement reaction
c.  redox reaction
d.  combustion reaction
e.  synthesis reaction
f.  decomposition reaction
g.  acid – base reaction
h.  precipitation reaction

 

C3 H8   +  O2   -->  CO2   +  H2 O is an example of  _________.

HNO3   +  Fe  -->  Fe(NO3 )2   +  H2   is an example of  _________.

HCl  +  KOH  -->  KCl  +  H2 O  is an example of  _________.

H2   +  I2   -->  HI   is an example of  _________.

AgNO3   +  NaCl  -->  AgCl  +  NaNO3    is an example of  _________.

 

6.   In regards to the chemical equations shown in question 5.  [10 points]

a.  identify a redox reaction.

b.  write the oxidation half-reaction

c.  what is the oxidation number of the chemicals that are oxidized

d.  write the reduction half-reaction

e.  what is the oxidation number of the chemicals that are reduced