Hard Water Analysis - EDTA Titration for Calcium Content

A blank is run where 15 drops of 0.03 M MgCl2 is titrated with EDTA using Erichrome Black T indicator in a buffer 10 solution.
Next a Calcium sample is titrated where 0.21 g of CaCO3 is dissolved in HCl and then excess HCl removed through boiling and then diluted to 500 mL with distilled water. The 15 drops of MgCl2 are used as well in this titration. 10 mL of the standard Ca solution is used.
Last tap water is titrated where 15 drops of 0.03 M MgCl2 and 22.0 mL of tap water.

Blank titration initial 3.4 mL final 8.62
Ca Sample titration initial 8.64 final 28.50 mL
Tap water Initial 28.53 mL Final 48.60 mL

Видео Hard Water Analysis - EDTA Titration for Calcium Content канала Scott Milam