8 points a write the balanced molecular equation for

(8 points)
a. Write the balanced molecular equation for the reaction.
2AgNO3(aq) + CaCl2(aq) = 2AgCl(s) + Ca(NO3)2(aq)
b. Write the net ionic equation for the reaction.
Ag+ + Cl- --> AgCl
c. How many grams of precipitate will form?
Moles of AgNO3 = (0.5)(0.1) = 0.05 moles
Moles of CaCl2 = (0.1)(0.5) = 0.05 moles
AgCl is limiting reagent
Moles of CaCl2 used = 0.05/2 = 0.025 moles
(0.05)(143.32) = 7.166 gm
d. What is the concentration of Ag + , NO
3
‒ , Ca 2+ , and Cl ‒ in the final solution (assume
volumes are additive).
Ag= 0 M as all AgNO3 is consumed
NO3= 0.05/(0.1+0.1) = 0.25 M
Ca2= 0.05/0.2 = 0.25 M
Cl=0.05/0.2 = 0.25 M
14. Based on oxidation number consideration, explain why carbon monoxide is
flammable but carbon dioxide is not. (4 points)
CO is able to react with oxygen to create CO2, but CO2 is fully oxidized. So it will be
unreactive with oxygen. Because the C in CO has a lower oxidation number then the C
in CO2, CO is more flammable.
15. The alcohol content in a 10.0 g sample of blood from a driver required 4.23 mL of
0.07654 M K
2
Cr
2
O
7
for titration. If the current legal limit of blood alcohol content is
0.08 percent by mass, should the driver be prosecuted for drunken driving? What is the
percent alchohol in the driver’s blood? (7 points)
3 C
2
H
5
OH (ethanol) + 2 K
2
Cr
2
O
7
+ 8 H
2
SO
4
→ 3 HC
2
H
3
O
2
+ 2
Cr
2
(SO
4
)
3
+ 2 K
2
SO
4
+ 11 H
2
O
Moles of K2Cr2O7 = 0.07654 x .00423 = 0.003237642 moles
0.003237642 x 3/2 = 0.0004856463 moles of eTOH
Molar mass of ethanol = 46.06867 g/ mol so mass of EtOH in 10.0 g
=0.0004856463 x 46.06867
= 0.0223730791 g in 10 g or 0.223730791 %
= .224 % ethanol
16. Write balanced chemical equations for the following: (8 points)
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Copyright © 2014 by Thomas Edison State College. All rights reserved.

a. A solution of sulfuric acid (battery acid) is neutralized with a solution of sodium
hydroxide.
H2SO4 + 2NaOH = 2H2O + Na2SO4
b. The combustion of iron metal produces iron(III) oxide (rust).
3Fe + O2 = Fe3O2
c. When sodium metal is dropped into water, it fizzes.
2Na + 2H2O = 2NaOH + H2
d. The science fair “volcano reaction” is produced by mixing sodium bicarbonate
(baking soda) with vinegar (a solution of acetic acid HC
2
H
3
O
2
).
NaHCO3 + CH3COOH = CH3COONa + H2O + CO2
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Copyright © 2014 by Thomas Edison State College. All rights reserved.