Complexometric determination of water hardness
Complexometric Determination of Water Hardness
9/12/2013
Abstract: Two sets of acid-base neutralization titrations were conducted for experimental analysis. The first set of titrations was to standardize a solution manufactured in the lab. An approximate solution of Na2EDTA of 0.004 M was titrated against a known solution of 1.000 g CaCO3/L to deter mine to exact molarity of the Na2EDTA.
Ca2+ + Na2EDTA → CaEDTA + 2Na+
The second set of titrations was to use the now standardized Na2EDTA solution to determine an unknown water sample’s hardness. The unknown water sample is # 89. Water’s hardness arises from metal ions with a charge of +2 or higher. So for this experiment, the previously stated reaction can be used as follows: (Unknown #89)2+ + Na2EDTA → (Unknown #89)EDTA + 2Na+
In conclusion, unknown sample #89 has a water hardness value of 209.5 ppm
Introduction:
The purpose of this experiment is to determine the hardness of a sample of water (#89). Water hardness can be evaluated by an acid-base neutralization titration. (When an acid and a base are placed together, they react to neutralize the acid and base properties, producing a salt.) From the Bronsted-Lowry acid-base reaction theory, the H+ cation of the acid combines with the OH- anion of the base to form water. In this titration experiment, there are no definitive acidic or basic agents being evaluated. This requires the use of the Lewis acid-base theory. Instead of defining acid-base reactions in terms of protons or other bonded substances, the Lewis definition defines a base (referred to as a Lewis base) to be a compound that can donate an electron pair, and an acid (a Lewis acid) to be a compound that can receive this electron pair. Similarly, in either type of acid-base neutralization experiment, an indicator is used to display when the solution is neutralized. The standardized Na2EDTA water solution is will be titrated against the unknown water sample
9/12/2013
Abstract: Two sets of acid-base neutralization titrations were conducted for experimental analysis. The first set of titrations was to standardize a solution manufactured in the lab. An approximate solution of Na2EDTA of 0.004 M was titrated against a known solution of 1.000 g CaCO3/L to deter mine to exact molarity of the Na2EDTA.
Ca2+ + Na2EDTA → CaEDTA + 2Na+
The second set of titrations was to use the now standardized Na2EDTA solution to determine an unknown water sample’s hardness. The unknown water sample is # 89. Water’s hardness arises from metal ions with a charge of +2 or higher. So for this experiment, the previously stated reaction can be used as follows: (Unknown #89)2+ + Na2EDTA → (Unknown #89)EDTA + 2Na+
In conclusion, unknown sample #89 has a water hardness value of 209.5 ppm
Introduction:
The purpose of this experiment is to determine the hardness of a sample of water (#89). Water hardness can be evaluated by an acid-base neutralization titration. (When an acid and a base are placed together, they react to neutralize the acid and base properties, producing a salt.) From the Bronsted-Lowry acid-base reaction theory, the H+ cation of the acid combines with the OH- anion of the base to form water. In this titration experiment, there are no definitive acidic or basic agents being evaluated. This requires the use of the Lewis acid-base theory. Instead of defining acid-base reactions in terms of protons or other bonded substances, the Lewis definition defines a base (referred to as a Lewis base) to be a compound that can donate an electron pair, and an acid (a Lewis acid) to be a compound that can receive this electron pair. Similarly, in either type of acid-base neutralization experiment, an indicator is used to display when the solution is neutralized. The standardized Na2EDTA water solution is will be titrated against the unknown water sample