TM 5-6630-215-12
(2) Method for Phenolphthalein “P” Alkalinity Test (0-500 mg/l).
(a) Add sample water to the line in the titration vial.
(b) Add 1 drop
of phenolphthalein indictor to the vial and
mix.
If the sample does not turn pink, the phenolphthalein alkalinity
is zero.
Proceed to total Alkalinity Test.
(c) If the sample does turn pink, fill the micro burette (para
2-11) with alkalinity titration reagent.
(d) Titrate the sample slowly with the alkalinity titration
reagent.
Swirl the vial gently during each addition.
When the sample
changes from pink to colorless, stop titrating and record the scale
reading from the micro burette barrel.
Multiply the number of major
micro burette divisions used by 10 to obtain the “P” alkalinity as
mg/l calcium carbonate (CaCO3).
NOTE
Save the sample for the Total Alkalinity test. Do
not refill the micro burette at this point.
(3) Total “T” Alkalinity Test (0-500 mg/l).
(a) Add to the sample on which the phenolphthalein alkalinity
has just been determined, 1 drop of total alkalinity indicator and
mix.
The color of the sample should be green at this point.
(b) Continue to slowly add alkalinity titration reagent left
in the micro burette after the phenolphthalein test to the titration
vial with swirling, until the green color of the sample changes to a
permanent pale purple.
(c) Record the total number of micro burette divisions used.
Multiply the total number of micro burette divisions used by 10 to
obtain the total
“T” alkalinity concentration as mg/l (CaC03).
b.
Low Range Chloride Test Kit Instructions (fig 2-14).
(1) Chlorides are present in all potable water supplies and in
sewage,
usually as a metallic salt.
When sodium is present in drink-
ing water, chloride concentrations in excess of 250 mg/l give a salty
taste..
If the chloride is present as a calcium or magnesium salt,
the taste detection level may be as high as 1000 mg/l chloride.
(a) Chloride is essential in the diet and passes through the
digestive system unchanged to become one of the major components of
raw sewage.
The wide use of zeolite in water softeners also contrib-
utes a large amount of chloride in sewage and wastewaters.
(b) High chloride concentrations in water are not known to
have toxic effects on man, though large amounts may act corrosively on
metal pipes and be harmful to plant life.
The maximum allowable
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