Exam 1
Lab Section
Name
Time Allowed = 50 Minutes
Points available = 90
1. List at least four observations of a chemical reaction and give an example of
each? (8 points)
2. Write a molecular equation, ionic and net ionic for the reaction of iron (II) sulfate
and potassium phosphate? (8 points)
3. Circle the insoluble salts: CuSO4, Co(NO3)3, CaCO3, Ni3(PO4) 2, BaCl2, BaSO4 ,
CoCl2, Fe(OH)3 (4 points)
4. ‘If 2 drops are good, 20 drops are better” explain why this reasoning is not logical
when using phenolphthalein as an indicator? b) Give one factor that needs to
consider when choosing an indicator (5 points)
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5. Describe the following: (8 points
a. Titration
b. Qualitative Analysis
c. end point
d. equivalence point?
6. To synthesize Pb(NO3) 2 (m.w =331.2) the following reaction can be carried out:
(8 pts)
PbO(s) + 2HNO3(aq) → Pb(NO3)2(aq) + H2O
In this reaction a yield of 86.0% can be obtained, in order to have 5.0 g of product,
how many grams of PbO (m.w = 223.2) would be needed ? (Assume there is
sufficient nitric acid)
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7. Suppose you suspected that a certain solution contained ammonium ions, what
simple chemical test with equation could you perform that would tell you that
your suspicions were correct? (5 points)
8. Name the following: a) NaHCO3 b) Na2S, c) K2SO3 and give the gases that are
formed if HCl is added to each (6 points)
9. You have 2 test-tubes containing MgCl2 and Mg(NO3) 2 , describe how you would
differentiate between the two using chemical reactions, give equations? (8 points)
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10. Complete the following equations and then determine what is the driving force in
each reaction? (12 points)
a. CuCl2+Na2CO3 →
b. K2SO3 + H2SO4 →
c. NaClO + HCl→
d. Ba(OH) 2 + HNO3→
11. Barium sulfate (molar mass =233.43) is made from reacting barium nitrate (molar
mass 261.25) with sodium sulfate (molar mass = 142.04). An experiment was
performed which reacted 75g of barium nitrate and an excess of sodium sulfate,
after collecting and drying the product 64.5g of barium sulfate were obtained.
Calculate the theoretical and percentage yield of barium sulfate. (10 points)
12. What color is phenolphthalein in basic and acidic solution? (2 points)
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13. Which of the following metals could displace Cu ions from copper solution? (2
pts)
a. Zn
b. Pt
c. Au
d. Ag
14. What color are barium ions in the Bunsen flame? (2 points)
15. A reaction requires 17.6g of chloroform (CHCl3, d =1.446g/ml) What volume in
ml should be used? (2 points)
a.
b.
c.
d.
e.
17.6
25.4
12.2
19.0
00822
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