GB/T 21994.6-2008 English PDF

US$139.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email.
GB/T 21994.6-2008: Chemical analysis of magnesium fluoride -- Part 6: Determination of silica content -- Molybdenum blue photometric method
Status: Valid

Standard ID	USD	BUY PDF	Lead-Days	Standard Title (Description)	Status
GB/T 21994.6-2008	139	Add to Cart	3 days	Chemical analysis of magnesium fluoride -- Part 6: Determination of silica content -- Molybdenum blue photometric method	Valid

Similar standards

GB/T 20975.29   GB/T 20975.28   GB/T 20975.30   GB/T 21994.3   GB/T 21994.4   GB/T 21994.2   

Basic data

Standard ID: GB/T 21994.6-2008 (GB/T21994.6-2008)
Description (Translated English): Chemical analysis of magnesium fluoride -- Part 6: Determination of silica content -- Molybdenum blue photometric method
Sector / Industry: National Standard (Recommended)
Classification of Chinese Standard: H12
Classification of International Standard: 77.040.30
Word Count Estimation: 6,672
Date of Issue: 2008-06-09
Date of Implementation: 2008-12-01
Quoted Standard: GB/T 21994.1-2008
Regulation (derived from): National Standard Approval Announcement 2008 No.9 (Total No.122)
Issuing agency(ies): General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China
Summary: This standard specifies the determination of magnesium fluoride in silica. This section applies to the determination of magnesium fluoride in silica. Measuring range: �� 1. 00%.

GB/T 21994.6-2008: Chemical analysis of magnesium fluoride -- Part 6: Determination of silica content -- Molybdenum blue photometric method

---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Chemical analysis of magnesium fluoride Part 6. Determination of silica content Molybdenum blue photometric method. ICS 77.040.30 H12 National Standards of People's Republic of China Chemical analysis of magnesium fluoride Part 6. Determination of silica content Molybdenum blue spectrophotometric method Posted 2008-06-09 2008-12-01 implementation Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China Standardization Administration of China released

Foreword

GB/T 21994 "Chemical analysis of magnesium fluoride" is divided into eight sections. --- Part 1. Preparation and storage of test samples; --- Part 2. Determination of the weight of water in the wet method; --- Part 3. Determination of distillation of fluorine content - thorium nitrate volumetric method; --- Part 4. Determination of magnesium content - EDTA volumetric method; --- Part 5. Determination of calcium content by flame atomic absorption spectrometry; --- Part 6. Determination of silicon dioxide content - Molybdenum blue spectrophotometric method; --- Part 7. Determination of iron oxide content phenanthroline spectrophotometry; --- Part 8. Determination of sulfate content of barium sulfate gravimetric method. Part is divided into 6 sections. This part is proposed by the China Nonferrous Metals Industry Association. The non-ferrous metal part by the National Standardization Technical Committee. This section is Hunan Nonferrous fluorine chemical limited liability company, China Nonferrous Metals Industry Institute of Standards Metrology and Quality is responsible for drafting. This section is drafted. Hunan Nonferrous fluorine chemical limited liability company. Participated in the drafting of this section. Fluoride Chemicals Co., Ltd., Silver fluoride limited liability company. The main drafters of this section. Li Zhijian, Liao Zhihui, Chen Xiang Yu, Zhu Liang, Xu Jin Xue, Wang Jianping, Guo Xianhui, Bo, Li Ye. Chemical analysis of magnesium fluoride Part 6. Determination of silica content Molybdenum blue spectrophotometric method

1 Scope

This section provides the determination of magnesium fluoride silica. This section applies to the determination of magnesium fluoride in silica. Measuring range. ≤1.00%.

2 Normative references

The following documents contain provisions which, through reference in this text, constitute provisions of this part. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this section, however, encourage the parties to this part of the research agreement Whether the latest versions of these documents. For undated references, the latest edition to adapt to this section. GB/T 21994.1-2008 Chemical analysis of magnesium fluoride - Part 1. Sample Preparation and Storage

3 Method summary

Sample with sodium carbonate and boric acid flux melt, hydrochloric acid. Points to take the test solution between pH0.85 ~ pH0.90, silicon and molybdic acid Salt formation yellow silicon molybdenum heteropoly acid. In the high acidity sulfuric acid medium, the reducing agent is a Silicon molybdenum blue, in the spectrophotometer at a wavelength of 620nm Measuring the absorbance.

4 Reagents

4.1 anhydrous sodium carbonate. 4.2 boric acid. 4.3 hydrochloride (3mol/L). 4.4 ammonium molybdate solution (100g/L). 4.5 sulfate (1 + 1). 4.6 ascorbic acid solution (25g/L). When using the preparation. 4.7 silica standard stock solution. Weigh 0.5000g finely pre-burning 1h at 1000 ℃, and cooled to room in the dryer Temperature silica (99.9%), placed in a platinum crucible, to which was added 5g of anhydrous sodium carbonate in the (4.1), mix well with a platinum spoon, set high Oven temperature at 950 ℃ carefully melted (about 10min), then cool, water was added to the crucible, heated slowly to dissolve completely. The solution was cooled CAUTION moved 1000mL volumetric flask, dilute to volume, and mix. Immediately poured into a polyethylene bottle. This solution 1mL containing 0.500mg two Silicon oxide. 4.8 silica standard solution. Pipette 50.00mL silica standard stock solution (4.7) in 500mL flask, diluted with water To the mark, and mix. Immediately transferred to plastic bottles. This solution 1mL containing 0.0500mg silica. The solution was formulated before use now.

5 instruments and equipment

5.1 platinum dish. flat, diameter 70mm, height 35mm, with platinum cover. 5.2 EAF. to control the temperature at 550 ℃ ± 25 ℃. 5.3 Furnace temperature. the temperature can be controlled at 850 ℃ ± 25 ℃. 5.4 pH meter. with a glass electrode. ......

Image     

Tips & Frequently Asked Questions:

Question 1: How long will the true-PDF of GB/T 21994.6-2008_English be delivered?

Answer: Upon your order, we will start to translate GB/T 21994.6-2008_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. The lengthier the document the longer the lead time.

Question 2: Can I share the purchased PDF of GB/T 21994.6-2008_English with my colleagues?

Answer: Yes. The purchased PDF of GB/T 21994.6-2008_English will be deemed to be sold to your employer/organization who actually pays for it, including your colleagues and your employer's intranet.

Question 3: Does the price include tax/VAT?

Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countries

Question 4: Do you accept my currency other than USD?

Answer: Yes. If you need your currency to be printed on the invoice, please write an email to Sales@ChineseStandard.net. In 2 working-hours, we will create a special link for you to pay in any currencies. Otherwise, follow the normal steps: Add to Cart -- Checkout -- Select your currency to pay.