W Engineering EXAM II FALL 2010
PROBLEM
#-25
NAME
Points
WRITE ANSWERS TO THE FOLLOWING QUESTIONS ON THE NEXT PAGE, SHOW YOUR
WORK. These questions are repeated on the next page for your convenience.
a)
(Spts) All of the alkalinity is comprised of HCOa. Why does the value for alkalinity differ
fiom ihe concentration of HGOg? Provide calculations to support your answer.
b) (1zpts) ls the water saturated with calcium sulfate (CaSOr)? Provide calculations
to
support your answer.
c) (Spts) Will calcium carbonate (CaGO3) precipitate from this sample? Provide
calculations to support your answer.
d) (3pts) Will this water cause corrosion? Provide calculations to support your answer.
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GW Engineering EXAM II FALL 2010
PROVI
D
E CALC
U
LATION S AN D ANSWE RS TO
IP
ROBLEIT,I:LHERE
a) (spts) All of the alkalinity is comprised of HCO3. Why does the value for alkalinity differ
from the concentration of HCO3? Provide calculations to support your answer.
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b) (12pb) ls the water saturated with calcium sulfatl
support your answer.
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(CaSO4)? Provide calcutations to
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c) (spts) Will calcium carbonate
(CaCOa) precipitate from this sample? Provide
calculations to support your answer.
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d) (3pts) will this water cause corrosion? Provide calculations
R1roo.,- Ir'&*v
-3,
r = il-\ *9v\:' * 1'31-7'7?
to support ,ouJ il- tJi
-"*''
2 [:.r*)-?,3-1= 8,o8
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NAME
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NAME
GW Engineering EXAM II FALL 2010
Carbonate Equitribriun'l Constants as a Function of Ternperature
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