What is the difference between phenolphthalein alkalinity and total alkalinity?

What is the difference between phenolphthalein alkalinity and total alkalinity?

Phenolphthalein alkalinity measures the hydroxides and half the carbonates at a pH 8.3. Total alkalinity measures all carbonate, bicarbonate, and hydroxide alkalinity at a pH 4.5 (approximately).

Are alkalinity and total alkalinity the same?

Total alkalinity is primarily bicarbonate, carbonate, and hydroxide, along with a few others like cyanurate alkalinity. When acid is added, these alkali have the ability to neutralize some of the acid. The more alkalinity you have, the more acid it takes to reduce pH.

What is meant by phenolphthalein alkalinity?

phenolphthalein alkalinity (FEE-nol-THAY-leen) The alkalinity in a water sample measured by the amount of standard acid required to lower the pH to a level of 8.3, as indicated by the change in color of phenolphthalein from pink to clear.

Can we use phenolphthalein indicator for determination of total alkalinity justify?

Like acidity, there are different ways to measure and report alkalinity; The first is to titrate the water with acid titrant to the phenolphthalein end point. This is called the phenolphthalein alkalinity….

Classification	Alkalinity (mg CaCO3 /L)
sensitive	between 10 and 20
not sensitive	above 20

What is difference between pH and total alkalinity?

pH is the abbreviation for “potential hydrogen” and the reading indicates the concentration of hydrogen ions in the water. Basically, it is the measure of how acidic or basic (alkaline) the water is. Total alkalinity is the measure of how stable the pH is.

What is the difference between total hardness and total alkalinity?

Alkalinity refers to the total amount of bases in water expressed in mg/l of equivalent calcium carbonate. Hardness is the concentration of metal ions (primarily calcium and magnesium) expressed in mg/l of equivalent calcium carbonate.

What causes phenolphthalein alkalinity?

Other salts of weak acids, such as borate, silicates, ammonia, phosphates, and organic bases from natural organic matter, may be present in small amounts. Alkalinity, by convention, is reported as mg/L CaCO3 since most alkalinity is derived from the weathering of carbonate minerals.

Why is alkalinity expressed as CaCO3?

Why is alkalinity reported as “mg/L as CaCO3”? Units of mg/L are a “mass dissolved in a liquid.” Reporting alkalinity as “mg/L as CaCO3” specifies that the sample has an alkalinity equal to that of a solution with a certain amount of calcium carbonate (CaCO3) dissolved in water.

What is M and P alkalinity?

p alkalinity is the measurement of alkalinity given by hydroxide ions and half of the carbonate alkalinity. m alkalinity is the measurement of alkalinity given by hydroxide ions and total carbonate alkalinity. Indicator. Phenolphthalein indicator is used to determine p alkalinity.

What is phenolphthalein alkalinity?

Water that has a pH >8.3 is said to have “phenolphthalein alkalinity,” which is alkalinity due primarily to the presence of carbonate or hydroxide ions. Many water samples have little or no phenolphthalein alkalinity, and therefore remain colorless after adding this indicator to the sample water.

What is P alkalinity?

>P alkalinity or Phenolphthalein alkalinity is the measurement of amount carbonate and hydroxide using titrating water sample with acid of a known concentration and using Phenolphthalein indicator. >Here, “P” refers to the pH indicator Phenolphthalein indicator. >P-alkalinity is measured down to a pH of 8.3.

What is the range of pH for alkaline?

The following endpoints, corresponding to total alkalinity concentrations, are suggested in Standard Methods (1992): pH = 5.1 for total alkalinities of about 50 mg/L, pH = 4.8 for 150 mg/L, and 4.5 for 500 mg/L.

Why does phenolphthalein give the total hydroxide and half the carbonate level?

Since CO2- 3 is dibasic, only half of it is neutralized at the phenolphthalein endpoint. Thus, phenolphthalein alkalinity gives the total hydroxide and half the carbonate level.