LaMotte ALKALINITY TOTAL & PHENOLPHTHALEIN LLI 4533 - Manual

ALKALINITY
TOTAL & PHENOLPHTHALEIN
DROP COUNT METHOD
CODE LLI • 4533
QUAN TITY CON TENTS CODE
100 BCG-MR Tablets T-2311-J
100 Phenolphthalein Tablets T-2246-J
50 mL Sulfuric Acid, 0.1N 6111-H
1 Titration Tube, 5 mL 0647
1 Pipet, plain 0352
To order a complete set of refill reagents, order as R-LLI-4533. To order
individual reagents or test components, use the specified code number.
PRO CE DURE
PHENOLPHTHALEIN (P) AL KA LIN ITY
1.
Fill the titration tube (0647) to 5 mL line with sample water.
2.
Add one Phenolphthalein Tablet (T-2246). Cap and shake until
disintegrated. If a red color does not develop the P Alkalinity is zero. If
sample turns red, proceed to Step 3.
3.
Fill the pipet (0352) with the Sulfuric Acid, 0.1N (6111). While gently
swirling the tube, add Sulfuric Acid, 0.1N (6111) drop by drop until
color changes from red to colorless. Count the drops added.
4.
Calculate results:
No. of drops in Step 3 x 50 = ppm Phenolphthalein Alkalinity
expressed as ppm Calcium Carbonate (CaCO
3
)
TO TAL (T) AL KA LIN ITY
1.
Fill the titration tube (0647) to 5 mL line with sample water.
2. Add one BCG-MR Tablet (T-2311). Cap and shake until disintegrated.
Sample color will turn green.
3.
Fill the pipet (0352) with the Sulfuric Acid, 0.1N (6111). While gently
swirling the tube, add Sulfuric Acid, 0.1N (6111) drop by drop until
color changes from green to pink. Count the drops added.
4.
Calculate results:
No. of drops in Step 3 x 50 = ppm Total Alkalinity
expressed as ppm Calcium Carbonate (CaCO
3
)
CAL CU LA TION OF AL KA LIN ITY RE LA TION SHIPS
The results obtained from the Phenolphthalein and Total Alkalinity
determinations offer a means for the stoichiometric classification of the
three principal forms of alkalinity present in many water supplies. The
classification attributes the entire alkalinity to bicarbonate, carbonate and
hydroxide, and assumes the absence of other weak acids of inorganic or
organic composition, such as silicia, phosphoric and boric.
This classification system assumes the incompatibility of hydroxide and
bicarbonate alkalinities in the same sample. Since the calculations are on a
stoichiometric basic, ion concentrations in the strictest sense are not
represented in the results.
According to this scheme:
A.
Carbonate alkalinity is present when the phenolphthalein alkalinity is
not zero but is less than the total alkalinity.
B.
Hydroxide alkalinity is present if the phenolphthalein alkalinity is more
than one-half the total alkalinity.
C.
Bicarbonate alkalinity is present if the phenolphthalein alkalinity is less
than one-half the total alkalinity.
RELATIONSHIPS BETWEEN
PHENOLPHTHALEIN ALKALINITY, TOTAL ALKALINITY,
CARBONATE ALKALINITY, AND HYDROXIDE ALKALINITY.
Hydroxide Carbonate Bicarbonate
Result of Alkalinity as Alkalinity as Alkalinity as
Titration CaCO3 CaCO3 CaCO3
P=0 0 0 T
P< 1
2
T 0 2P T-2P
P= 1
2
T 0 2P 0
P> 1
2
T 2P-T 2 (T-P) 0
P=T T 0 0
LIB ERTY LABS, INC.
400 JE RI CHO TURN PIKE • JE RI CHO • NEW YORK • 11753