Polymetron 9210 - Reagent Preparation; Reagent 1 M - Molybdate (2 Liters); Reagent 1 A - Nitric Acid (2 Liters); Reagent 2 - Oxalic Acid

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Installation
4.11 Reagent preparation
The four reagent solutions, and the calibration solution should be prepared as per the following
instructions. Before refilling the five canisters with 2 liters of their respective solution, they
should be thoroughly rinsed with ultra pure water.
Note: These solutions are best prepared with the aid of a magnetic stirrer.
WARNING
Read the Material Safety Data Sheets (MSDS) on page 77 and wear protective goggles
and clothes before using chemical products.
4.11.1 Reagent 1M - Molybdate (2 liters)
• Rinse a 2 liter volumetric flask three times with ultra pure water
• Fill two-thirds of the flask with ultra pure water which has less than 5 ppb of SiO
2
• Stirring continuously for about 5 minutes, gently dissolve 110g of the sodium dihydrate
molybdate in the water. The turbidity of the solution should be very low
• Top up the solution to 2 liters with additional ultra pure water, and transfer the solution to
the canister labelled R1M
4.11.2 Reagent 1A - Nitric acid (2 liters)
• Rinse a 2 liter volumetric flask three times with ultra pure water
• Fill two-thirds of the flask with ultra pure water which has less than 5 ppb of SiO
2
• Stirring continuously for about 5 minutes, gently pour 300mL of nitric acid into the water.
The solution should be clear
• Top up the solution to 2 liters with additional ultra pure water, and transfer the solution to
the canister labelled R1A
4.11.3 Reagent 2 - Oxalic acid
• Rinse a 2 liter volumetric flask three times with ultra pure water
• Fill two-thirds of the flask with ultra pure water which has less than 5 ppb of SiO
2
• Stirring continuously for about 5 minutes, gently dissolve 80g of oxalic acid in the water
• Top up the solution to 2 liters with additional ultra pure water, and transfer the solution to
the canister labelled R2
Label Composition Concentration
R1M Sodium dihydrate molybdate Na
2
MoO
4
.2H
2
O >99%, neat
(analytical quality; Fluka# 71756, Merck# 106521 or equivalent)
55 g/L
Label Composition Concentration
R1A Nitric Acid, HNO
3
(65% Puriss analytical grade; Fluka# 84380 or
equivalent)
150 mL/L, 15% V/V
Label Composition Concentration
R2 Oxalic Acid (Puriss analytical grade; Fluka# 75700 or equivalent) 40 g/L