horiba TPNA-500, Инструкция по эксплуатации

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Preparation for Operation
36

Preparing L-ascorbic acid aqueous solution [Reagent D]
1.
Measure 6 g of L(

) - ascorbic acid (special grade).
2. Pour approximately 200 mL of pure water into a container.
3.
Dissolve the above measured reagent completely in this container.
4. Add pure water to make it a total of 250 mL.

Preparing mixed reagent (ammonium molybdate

potassium antimonyl
tartrate sesquihydrate) [Reagent E]
Note

Do not heat the reagent when dissolving it (the reagent will be crystallized).

If the reciprocal sensitivity and accuracy of the balance used for weighing are inadequate,
increase the amount of solution to be measured and prepare the reagent in proportion to the
amount (example: measure 12 g of ammonium molybdate and 0.3 g of potassium antimonyl
tartrate sesquihydrate, and then dilute them with pure water to make it a total of 1 L).
1. Measure 3 g of ammonium molybdate (special grade) and 0.075 g of potassium
antimonyl tartrate sesquihydrate.
2.
Pour approximately 200 mL of pure water into a container.
3.
Dissolve the above measured reagent completely in this container.
4.
Add pure water to make it a total of 250 mL.

Preparing hydrochloric acid solution [Reagent F]
1. Measure 35 mL of hydrochloric acid (special grade: 35% to 37

of hydrochloric
acid) in a measuring cylinder.
2. Measure 210 mL of pure water in a measuring cylinder and pour it into a heat-
resistant container.
3.
Slowly pour hydrochloric acid into the container while agitating pure water.
4.
Cool the reagent to room temperature.
WARNING
Wear protective goggles and gloves when preparing hydrochloric acid solution.
Dissolving the reagent generates hydrochloric vapor and heat.
• Dissolve the reagent in a well-ventilated area such as a draft chamber.
• Always pour hydrochloric acid into pure water. Never pour pure water into hydrochloric acid.
• When dissolving the reagent, cool the container with water or ice as necessary.
• If it comes in contact with your skin, rinse it off well with running water.
• If it gets in your eyes, rinse it off well with running water, and then immediately consult a doctor.