a water sample is not alkaline to phenolphthalein.however 100ml of the sample on titration with 0.02 N HCL required 15.0 ml to obtain end point using methyl orange as indicator what are the types and amount of alkalinity present in the sample
Answers
Answer:
Using dye indicators measure phenolphthalein alkalinity and total alkalinity. Calculate
hydroxide, carbonate and bicarbonate alkalinity.
(2) Measure mineral and phenolphthalein acidity
Background:
(i) Alkalinity:
The alkalinity of the water is a measure of its capacity to neutralize acids. The alkalinity
of natural waters is due primarily to the salts of week acids. Bicarbonates represent the major
form of alkalinity. Alkalinity can be expressed as follows:
Alkalinity (mol/L) = [HCO3
-
] + 2 [CO3
2-] + [OH-
] – [H+
] (1)
Figure 1 presents the carbonate speciation diagram at different pH values. Waters rich in
bicarbonates (HCO3
-
) have high acid neutralizing capacity (high alkalinity).
Figure 1. Carbonate Species
Alkalinity is measured by titrating a sample with acid. A titration curve of a bicarbonate
Answer:
150ppm CaCo3 equivalent
Explanation:
P = V1 /V *Z *50*1000 ppm CaCo3 equivalent
P = 15 /100 *0.02*50*1000
P = 150 ppm CaCo3 equivalent