Electro-Chemical Devices (ECD) CA6 Hardness Analyzer - Manual (Page 35)

5.0 REAGENTS PREPARATION
Each analyte uses its own set of reagents to develop the distinctive color for measurement. The recipes
for the specific reagents required for this measurement are listed in Section 11.4 at the end of the
manual.
Each recipe details the chemicals used and the procedures used to produce the reagent.
Read all MSDS data sheets before preparing the reagents.
Use good laboratory technique. Wear safety goggles, gloves and protective clothing when preparing the
reagents, calibration solutions or cleaning solutions.
Mind all Hazard and Poison labels
Pre-made reagents and solutions are available from ECD. The part #s for the reagents can be found in
the recipe next to the reagent name and in section
9.3 Accessories and Spare Parts . Several of the
reagents are listed as Hazardous Shipping Materials; these materials are only available for shipment
domestically inside the USA.
Reagent 1
Cresolphthalein Solution
Part Number# 2010037-1
For 1 Liter preparation:
Name
Quantity
Hydrochloric Acid 37%, ACS Reagent
CAS Number: 7647-01-0
2.83 ml/L
o-Cresolphthalein Complexone
CAS Number: 2411-89-4
0.075 g/l
Clean all equipment with DI water before use.
Dissolve o-cresolphthalein in 2.83 ml of the concentrated hydrochloric acid. It may take a minute or so.
Fill a 1 liter volumetric flask to 2/3rds capacity with DI water. When dissolved slowly add the
Cresolphthalein HCl solution to the water while stirring the solution. Fill the volumetric flask to the
gauge line (1 liter). Transfer to the reagent 1 container provided with the analyzer.
Reagent 2
Ethanolamine solution
Part Number# 2010038-1
For 1 Liter preparation:
Name Quantity
Ethanolamine, ACS Reagent
CAS Number: 141-43-5
200 ml/L
Deionized Water 800 ml
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