HOME Cart(0) Quotation About-Us Policy PDFs Standard-List
www.ChineseStandard.net Database: 189760 (18 Oct 2025)

GB 4481.2-2010 English PDF

US$369.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email.
GB 4481.2-2010: National food safety standards of food additives tartrazine aluminum lake
Status: Valid

GB 4481.2: Evolution and historical versions

Standard ID	Contents [version]	USD	STEP2	[PDF] delivered in	Standard Title (Description)	Status	PDF
GB 4481.2-2010	English	369	Add to Cart	3 days [Need to translate]	National food safety standards of food additives tartrazine aluminum lake	Valid	GB 4481.2-2010
GB 4481.2-1999	English	439	Add to Cart	4 days [Need to translate]	Food additive--Tartrazine aluminum lake	Obsolete	GB 4481.2-1999
GB 4481.2-1994	English	RFQ	ASK	3 days [Need to translate]	Food additive- Tartrazine aluminum lake	Obsolete	GB 4481.2-1994

PDF similar to GB 4481.2-2010

Standard similar to GB 4481.2-2010

GB 1886.9 GB 1886.45 GB 1903.13 GB 1886.11 GB 1886.183 GB 4481.1

Basic data

Standard ID	GB 4481.2-2010 (GB4481.2-2010)
Description (Translated English)	National food safety standards of food additives tartrazine aluminum lake
Sector / Industry	National Standard
Classification of Chinese Standard	X42
Classification of International Standard	67.220.20
Word Count Estimation	16,155
Date of Issue	2010-12-21
Date of Implementation	2011-02-21
Older Standard (superseded by this standard)	GB 4481.2-1999
Regulation (derived from)	Ministry of Health Bulletin No. 19 of 2010
Issuing agency(ies)	Ministry of Health of the People's Republic of China
Summary	This Chinese standard applies to food additives and aluminum hydroxide reacts tartrazine food additive tartrazine aluminum lake.

GB 4481.2-2010: National food safety standards of food additives tartrazine aluminum lake

---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.
National food safety standards of food additives tartrazine aluminum lake National Food Safety Standard Food additive tartrazine aluminum lake Issued on. 2010-12-21 2011-02-21 implementation National Standards of People's Republic of China People's Republic of China Ministry of Health issued

Foreword

This standard replaces GB 4481.2-1999 "food additive tartrazine aluminum lake." This standard compared with GB 4481.2-1999, the main technical changes are as follows. - Added safety tips; - Modify the discrimination test methods; - Colorimetric method replicates allowable difference from 2% revised to 1.0%; - Canceled Chloride (NaCl) and sulfate (Na2SO4 to count) index; - Arsenic (As) is modified by chemical detection methods limit law atomic absorption spectrometry; - Cancel the heavy metals (as Pb) quality specifications; - Increase the lead (Pb) indicator and detection methods; - Barium (Ba) detection method to modify the barium sulfate precipitation assay limits. The Standard Annexes A and B are normative appendix. This standard replaces the standards previously issued as follows. --GB 4481.2-1999. National Food Safety Standard Food additive tartrazine aluminum lake

1 Scope

This standard applies to food additives produced by the effect of aluminum hydroxide and lemon food additive tartrazine aluminum lake.

2 Normative references

The standard file referenced in the application of this standard is essential. For cited documents with dates, only the date of Version applies to this standard. For undated references, the latest edition (including any amendments) applies to this standard.

3 formula and relative molecular mass

Formula 3.1 C16H9N4Na3O9S2 3.2 relative molecular mass 534.36 (according to 2007 international relative atomic mass) 4. Technical Requirements 4.1 Sensory requirements. comply with Table 1. Table 1 Sensory requirements Project requires test methods Yellow color By visual assessment of natural light. Organization Status powder 4.2 Physical indicators. to comply with Table 2. Table 2. Physical and chemical indicators Item Index Test Method Tartrazine (sodium salt dollars), w /% ≥ 10.0 Appendix A A.4 Loss on drying, w /% ≤ 30.0 Appendix A A.5 Hydrochloric acid and ammonia water insolubles, w /% ≤ 0.5 A.6 in Appendix A Deputy dye, w /% ≤ 0.5 Appendix A A.7 Arsenic (As)/(mg/kg) ≤ 3.0 Appendix A A.8 Lead (Pb)/(mg/kg) ≤ 10.0 A.9 in Appendix A Barium (Ba), w /% ≤ 0.05 Appendix A A.10

Appendix A

(Normative) Testing method A.1 Safety Tips Reagents The standard test methods used for toxic or corrosive, according to the relevant provisions of the operation, the operation need to be careful. If splashed on the skin should immediately wash with water, severe cases should be treated immediately. When using a volatile acid, to be carried out in a fume hood. A.2 General Provisions This standard reagents and water, did not indicate when the other requirements, refer to three analytical reagent and GB/T 6682-2008 specified water. Standard test solution required impurity standard solution, preparations and products at the time did not indicate other provisions, according to GB/T 601, GB/T 602, GB/T 603 regulations formulated and calibration. A.3 Identification Test A.3.1 Reagents and materials A.3.1.1 sulfuric acid. A.3.1.2 sulfuric acid solution. 120. A.3.1.3 hydrochloric acid solution. 13. A.3.1.4 sodium hydroxide solution. 100g/L. A.3.1.5 ammonium acetate solution. 1.5g/L. A.3.1.6 activated carbon. A.3.2 Instruments and Equipment A.3.2.1 Spectrophotometer. A.3.2.2 cuvette. 10mm. A.3.3 Identification method It should meet the following conditions. A.3.3.1 weighed sample of about 0.1g, add 5mL of sulfuric acid, at 50 ℃ ~ 60 ℃ water bath shaken from time to time, heated for about 5min, the solution was yellow. After cooling, the supernatant take 2 to 3 drops of drops, add 5mL water, the solution was yellow. A.3.3.2 weighed sample of about 0.1g, add 5mL sulfuric acid solution, heated and dissolved in a water bath, after the full mix, add up to 1 ammonium acetate solution 00mL, centrifugation the solution is not clarified. Then take this solution 1mL ~ 10mL, plus ammonium acetate solution equipped to 100mL, the measurement of the suction Luminosity values within the range of 0.2 to 0.7, a maximum absorption wavelength of this solution was 428 nm ± 2nm. A.3.3.3 weighed sample of about 0.1g, was added 10mL hydrochloric acid solution, heated in a water bath, so that most of the dissolved. Add 0.5g of activated carbon, Shake well, cooled and filtered. Take a colorless filtrate, add sodium hydroxide solution and after rendering aluminum reaction. A.4 Determination of lemon yellow aluminum lake A.4.1 Titanium trichloride titration (Arbitration Act) A.4.1.1 Method summary In acidic medium, tartrazine aluminum lake dye dissolve transitions into which the azo group is reduced and decomposed titanium trichloride, titanium trichloride according to standard The consumption of titration solution, calculate its content. A.4.1.2 Reagents and materials A.4.1.2.1 sodium bitartrate. A.4.1.2.2 titanium trichloride standard titration solution. c (TiCl3) = 0.1mol/L (now with the existing, method of preparation see Appendix B). A.4.1.2.3 cylinders loaded carbon dioxide. A.4.1.3 instruments and equipment A-- conical flask (a 500 mL); B-- Brown burette (50mL); C-- under glass bottle package black paper (2000mL); D-- containing 100g/L solution of ammonium carbonate and 100g/L ferrous sulfate solution container of an equivalent mixture (5000mL); E-- piston; F-- bottles; G-- washing bottle filled with water. Figure A.1 apparatus of FIG titanium trichloride titration A.4.1.4 analysis step Weigh about 1.0g sample (accurate to 0.0001g), placed in 500mL conical flask, 30g of sodium hydrogen tartrate and 200mL boiling Water, shake vigorously to dissolve, according to Figure A .1 instrument installed at the same time the level of carbon dioxide fed with titanium trichloride standard titration solution Droplet making natural color disappears as the end point. A.4.1.5 Calculation Results Lemon yellow aluminum lake (sodium salt meter) mass fraction 1w its value is expressed in%, according to formula (A.1) Calculated. 0) 4 /) (1000/( 1 × = m MVcw (A.1) Where. c - accurate titanium trichloride standard titration solution concentration value in units of moles per liter (mol/L); V - accurate value of the sample consumed titration of titanium trichloride standard titration solution volume in milliliters (mL); M - molar mass values tartrazine aluminum lake, in units of grams per mole (g/mol) [M (C16H9N4Na3O9S2) = 534.36]; m1 - mass value of the sample in grams (g). The results represent a decimal. The absolute difference between the parallel determination results is not more than 1.0% (mass fraction), the arithmetic mean value as a measurement result. A.4.2 Colorimetric method A.4.2.1 Method summary The samples with known content in lemon yellow standards were dissolved in water or in an aqueous medium, diluted to volume with ammonium acetate solution, in The maximum absorption wavelength, absorbance values were measured to calculate its content. A.4.2.2 Reagents and materials A.4.2.2.1 sodium bitartrate. A.4.2.2.2 ammonium acetate solution. 1.5g/L. A.4.2.2.3 lemon standards. ≥87.0% (mass fraction, measured according to A.4.1). A.4.2.3 instruments and equipment A.4.2.3.1 spectrophotometer. A.4.2.3.2 cuvette. 10mm. A.4.2.4 lemon preparation of standard solution Weigh about 0.25g lemon standards (accurate to 0.0001g), was dissolved in an appropriate amount of water, transferred to 1000mL volumetric flask, dilute with water Release to the mark. Draw 10mL, transferred to 500mL volumetric flask, add ammonium acetate solution was diluted to the mark, shake well and set aside. A.4.2.5 lemon yellow aluminum lake preparation of the sample solution Weigh about 0.5g sample (accurate to 0.0001g), was added 20mL of water and 2g of sodium hydrogen tartrate, heated to 80 ℃ ~ 90 ℃, dissolved After the solution transferred to 1000mL volumetric flask, dilute to the mark, shake. Draw 10mL transferred to 500mL volumetric flask, dilute with water Release to the mark. A.4.2.6 analysis step The standard solution and lemon yellow lemon yellow aluminum lake color sample solution were placed in 10mm cuvettes, with maximum absorption in the wavelength used Spectrophotometer respective absorbance values with ammonium acetate solution as the reference solution. A.4.2.7 Calculation Results Lemon yellow aluminum lake mass fraction 1w its value is expressed in%, according to formula (A.2) Calculated. 1 wmA Amw × = (A.2) Where. A - lemon yellow aluminum lake absorbance of the sample solution; Numerical m0-- lemon standard mass in grams (g); w 0-- lemon standard mass fraction%; Absorbance values A0-- lemon standard solution; Sample quality m-- value in units of grams (g). The results represent a decimal. The absolute difference between the parallel determination results is not more than 1.0% (mass fraction), the arithmetic mean value as a measurement result. A.5 Determination of loss on drying A.5.1 Analysis step Weigh about 2g sample (accurate to 0.001g), has been placed in the weighing bottle constant at 135 ℃ ± 2 ℃ constant temperature oven, in 135 ℃ ± 2 ℃ constant temperature oven drying to constant weight. A.5.2 Calculation Results Loss on drying mass fraction to 2w and its value is expressed in%, according to formula (A.3) Calculated. 2 × - = m mmw (A.3) Where. Numerical m2-- sample before drying mass in grams (g); m3-- sample dried to a constant mass values, expressed in grams (g). The results represent a decimal. The absolute difference between the parallel determination results is not more than 0.2% (mass fraction), the arithmetic mean value as a measurement result. A.6 Determination of hydrochloric acid and ammonia water insolubles A.6.1 Reagents and materials A.6.1.1 hydrochloric acid. A.6.1.2 hydrochloric acid solution. 37. A.6.1.3 ammonia solution. 496. A.6.1.4 silver nitrate solution. c (AgNO3) = 0.1mol/L. A.6.2 Instruments and Equipment A.6.2.1 sand core glass crucible. G4, a pore size of 5μm ~ 15μm. A.6.2.2 oven thermostat. A.6.3 Analysis step Join Weigh about 2g sample (accurate to 0.001g), placed in 600mL beaker, add 20mL of water and 20mL of hydrochloric acid, stir 300mL hot water, stir well, cover the surface of the dish, heating 30min, cooled at 70 ℃ ~ 80 ℃ water bath, use has been baked at 135 ℃ ± 2 ℃ to constant The amount G4 sintered glass filter crucible, with about 30mL of water to rinse the beaker insolubles to G4 sintered glass crucible to colorless after lotion, Washed first with aqueous ammonia solution 100mL, after washed with 10mL of hydrochloric acid solution, then washed with water until the silver nitrate solution was washed with a non-white test Precipitation, followed by 135 ℃ ± 2 ℃ constant temperature oven drying to constant weight. A.6.4 Calculation Results Hydrochloric acid and ammonia water insolubles mass fraction 6w and its value is expressed in%, according to formula (A.4) Calculated. 6 × = m mw (A.4) Where. m5 - quality dried insolubles values in grams (g); Sample quality m4-- value in units of grams (g). Calculation result to two decimal places. The absolute difference between the parallel determination results is not more than 0.10% (mass fraction), the arithmetic mean value as a measurement result. Determination A.7 deputy dye A.7.1 Method summary The components are separated by paper chromatography, eluted and quantified by spectrophotometry. A.7.2 Reagents and materials A.7.2.1 ethanol. A.7.2.2 n-butanol. A.7.2.3 sodium bitartrate. Acetone solution A.7.2.4. 1 1. A.7.2.5 ammonia solution. 496. A.7.2.6 sodium bicarbonate solution. 4g/L. A.7.3 Instruments and Equipment A.7.3.1 Spectrophotometer. A.7.3.2 chromatography filter paper. No. 1 in speed, 150mm × 250mm. A.7.3.3 chromatography tank. φ240mm × 300mm. A.7.3.4 micro injector. 100μL. A.7.3.5 Nessler colorimetric tube. 50mL glass grinding mouth stopper. A.7.3.6 glass frit funnel. G3, pore size of 15μm ~ 40μm. A.7.3.7 50mm cuvette. A.7.3.8 10mm cuvette. A.7.4 Analysis step A.7.4.1 paper chromatographic conditions A.7.4.1.1 developing solvent. n-butanol ethanol solution of aqueous ammonia = 623. A.7.4.1.2 Temperature. 20 ℃ ~ 25 ℃. A.7.4.2 preparation of the sample solution Weigh about 2g sample (accurate to 0.001g). Placed in a beaker, after adding the right amount of water and 5g of sodium hydrogen tartrate, dissolved by heating, shift Into 100mL volumetric flask, dilute to volume, shake up the sample solution concentration of 2%. A.7.4.3 wash out the sample preparation liquid With micro-injector draw 100μL sample solution evenly note on the bottom edge of the filter paper from a baseline of 25mm, a straight line, Its width on the filter paper does not exceed 5mm, length 130mm, with a hair dryer. The filter paper containing preformulated good Expand Chromatography tank agent, expand, filter paper dipped under the bottom edge of the agent level l0mm, to be solvent front line rose to 150mm or until the dye deputy Material separation satisfaction. Remove the filter paper chromatography, with cold dry. Blank filter paper under the same conditions to expand the blank paper must be used with the above steps to expand the adjacent paper on the same piece of filter paper Parts of the clipping. Deputy dye paper chromatography is shown in Figure A.2. The respective deputy dye expanded and made on a blank paper to each subsidiary colors corresponding parts of the paper in the same size cut, And cut into thin strips about 5mm × 15mm, and were placed in 50mL of Nessler colorimetric tube, accurately added to the acetone solution 5mL, shake 3min ~ 5min, then the exact solution of sodium bicarbonate was added 20mL, shake well, and then were naturally filtered G3 sintered glass funnel, and the filtrate We should clarify that no suspension. Respectively each subsidiary colors and blank eluate. In the respective maximum absorption wavelength of the dye deputy, with 50mm Cuvette wash the dye out of each sub-liquid measuring their absorbance on a spectrophotometer. Absorbance values measured on a spectrophotometer, with a mixture of 5mL and 20mL acetone solution of sodium bicarbonate solution as a reference solution. A.7.4.4 preparation of standard solution Draw sample solution 6mL 2% moved into 100mL volumetric flask, dilute to the mark, shake, and the solution as the standard solution. A.7.4.5 Preparation of standard eluate With micro-injector draw 100μL standard solution, uniform injection site on the bottom edge of the filter paper from a baseline of 25mm with a hair dryer Dry. The filter paper containing previously prepared well eluent chromatography tank to expand, to be solvent front line up 40mm, remove with cold Wind and dry, cut out all the dye partially deployed, according to A.7.4.3 subjected to extraction methods to obtain standard eluate. Colorimetric with 10mm Dish at the maximum absorption wavelength measured absorbance values. Meanwhile blank filter paper under the same conditions to start operating in the same manner after washing the absorbance value measured liquid. Baseline Main dye 130m m 150m m 250 mm 25m m Deputy dye Figure A.2 deputy dye paper chromatography schematic A.7.4.6 Calculation Results Deputy dye mass fraction 7w and its value is expressed in%, according to formula (A.5) Calculated. () () [] S bA bAbAw ss nn × - - - = ) 6/100) (( LL (A.5) Where. A1, An - each sub-dye eluate 50mm optical path length measured absorbance values; b1, bn - each sub-dye control blank eluate 50mm optical path length measured absorbance values; As - Standard eluate 10mm path length measured absorbance values; bs - standard control blank eluate 10mm path length measured absorbance values; 5 - converted to 10mm in number than the optical path length; 100/6 - Standard eluate converted into a 2% solution of the sample number ratio; S - mass fraction% of the sample. The results represent a decimal. The absolute difference between the parallel determination results is not more than 0.2% (mass fraction), the arithmetic mean value as a measurement result. A.8 Determination of Arsenic A.8.1 Method summary Lemon yellow aluminum lake after wet digestion to prepare a sample solution, determination of arsenic by atomic absorption spectrometry. A.8.2 Reagents and materials A.8.2.1 nitrate. A.8.2.2 sulfuric acid solution. 11. A.8.2.3 nitric acid - perchloric acid mixed solution. 31. A.8.2.4 arsenic (As) standard solution. According to GB/T 602 formulation and calibration, and then diluted formulated to contain the instrument according to the requirements of use Three corresponding concentration of arsenic standard solution. A.8.2.5 sodium hydroxide solution. 1g/L. A.8.2.6 sodium borohydride. 8g/L (solvent 1g/L sodium hydroxide solution). A.8.2.7 hydrochloric acid solution. 110. A.8.2.8 potassium iodide solution.200g/L. A.8.3 Instruments and Equipment A.8.3.1 atomic absorption spectrometer. A.8.3.2 Instrument Reference conditions. arsenic hollow cathode lamp analytical line wavelength. 193.7nm; slit. 0.5nm ~ 1.0nm; lamp current. 6 mA ~ 10mA. A.8.3.3 carrier gas flow rate. Argon gas 250mL/min. A.8.3.4 atomizer temperature. 900 ℃. A.8.4 Analysis step A.8.4.1 sample digestion Weigh about 1g sample (accurate to 0.001g), placed in 250mL triangular or round-bottomed flask, add 10mL ~ 15mL of nitric acid and 2mL Sulfuric acid solution, after shaking out of the nitrogen dioxide gas is heated over low heat, solution turned brown, stop heating, add 5mL nitric acid to cool - Perchloric acid mixture, strong heat until the solution became clear or slightly yellow, is still not as transparent, add 5mL nitric acid supplemented After cooling - perchloric acid mixed Solution, heating was continued until the solution is clear and colorless or slightly yellow and white smoke (to avoid charring dry out phenomenon occurs), heating was stopped and allowed to cool after 5mL water heated to boiling, remove residual nitric acid - perchloric acid (if necessary, can be combined with water to boil once), continue heating until white smoke occurred, Paul Holding 10min, transferred to 100mL volumetric flask After cooling (if the solution appears cloudy, precipitation or mechanical impurities to be filtered), diluted with hydrochloric acid solution Volume. At the same time, prepare a blank solution in the same manner. A.8.4.2 Determination Measure 25mL sample solution after digestion to 50mL volumetric flask, add 5mL potassium iodide solution with hydrochloric acid solution was diluted to volume, shake, Stand for 15min. At the same time in the same manner to prepare a blank solution blank test solution. Turn on the instrument, and the instrument is fully preheated arsenic hollow cathode lamp, a stable baseline, with a solution of sodium borohydride as hydride reduction occurs Agent to order standard blank, standard solution, sample solution and the blank test sample solution, according to computer instructions injections, respectively. End of test After the computer automatically generate the curve and deduct the arsenic concentration of the sample solution after sample blank, enter sample information (name, sample weight, Dilution volume, etc.), automatically converted from arsenic content in the sample. The absolute difference between the parallel determination results is not more than 0.1mg/kg, the arithmetic mean as a measurement result. A.9 Determination of Lead A.9.1 Method summary Lemon yellow aluminum lake after wet digestion to prepare a sample solution, Determination of lead by atomic absorption spectrometry. A.9.2 Reagents and materials A.9.2.1 Lead (Pb) standard solution. According to GB/T 602 formulation and calibration, and then according to the requirements of the instrument used in diluted formulated to contain Three corresponding concentration of lead standard solution. A.9.2.2 sodium hydroxide solution. 1g/L. A.9.2.3 sodium borohydride. 8g/L (solvent 1g/L sodium hydroxide solution). A.9.2.4 hydrochloric acid solution. 110. A.9.3 Instruments and Equipment A.9.3.1 atomic absorption spectrometer. A.9.3.2 Instrument Reference conditions. GB 5009.12-2010 third flame atomic absorption spectrometry. A.9.4 Analysis step A.8.4.1 can be directly used in the sample solution and blank solution. Press GB 5009.12-2010 third flame atomic absorption spectrometry operations. The absolute difference between the parallel determination results is not more than 1.0mg/kg, the arithmetic mean as a measurement result. Determination of barium A.10 A.10.1 Method summary Lemon yellow aluminum lake through dry after digestion process to prepare the sample solution, a solution of barium compared to the standard, as barium sulfate turbidity limit test. A.10.2 reagents and materials A.10.2.1 sulfuric acid. A.10.2.2 anhydrous sodium carbonate. A.10.2.3 hydrochloric acid solution. 13. A.10.2.4 sulfuric acid solution. 119. A.10.2.5 barium standard solution. barium chloride (BaCl2 · 2H2O) 177.9mg, dissolved in water and dilute to 1000mL. Per ml 0.1 milligrams of barium (0.1mg/mL). A.10.3 preparation of the sample solution Weigh about 1g sample (accurate to 0.001g), placed in a platinum crucible or a ceramic crucible, add a small amount of sulfuric acid wetting, slowly heating, Try to make almost all of carbonization at low temperatures. After cooling, plus 1mL of sulfuric acid, heated slowly to hardly occurs until the sulfuric acid vapor, Placed in a furnace at 800 ℃ burning 3h. After cooling, add 5g anhydrous sodium carbonate were thoroughly mixed with official placed in a furnace at 860 ℃ burning 15min, after cooling, add water, 20mL, heated in water bath, dissolve the melt. After cooling and filtration, the filter was washed with water The residue was washed paper to sulfate was not reacted. The paper is then moved together with the filter paper and residue beaker, add 30mL salt Acid solution, shake it well boiled. After cooling and filtration, the residue was washed with 10mL of water on the filter paper. The washings were combined with the filtrate, in Evaporated to dryness on a water bath. The residue was dissolved 5mL water added, if necessary, by filtration, the solution added 0.25mL of hydrochloric acid, after mixing, add water To 25mL with a sample solution. A.10.4 turbidity standard solution preparation Take 5mL barium standard solution, add a solution of hydrochloric acid 0.25mL. Add water to 25mL, as a standard turbidity solution. A.10.5 Analysis steps In each sample solution and the standard solution of sulfuric acid plus 1mL mixed turbidity solution, placed 10min, the sample solution must not exceed the degree of opacity By standard turbidity solution is qualified.

Appendix B

(Normative) The method of preparation of titanium trichloride standard titration solution B.1 Reagents and materials B.1.1 hydrochloric acid. B.1.2 ferrous ammonium sulfate. B.1.3 ammonium thiocyanate solution.200g/L. B.1.4 sulfuric acid solution. 11. B.1.5 titanium trichloride solution. B.1.6 potassium dichromate standard titration solution. c (1/6K2Cr2O7) = 0.1mol/L, according to GB/T 602 Preparation and calibration. B.2 instruments and equipment Figure A.1. Formulated B.3 titanium trichloride standard titration solution B.3.1 preparation Take 100mL titanium trichloride solution and 75mL of hydrochloric acid placed 1000mL brown volumetric flask, with boiled and cooled to room temperature Diluted with water to the mark, shake, immediately poured into a dark bottle under the mouth, under the protection of stored carbon dioxide gas. B.3.2 Calibration Weigh about 3g (accurate to 0.0001g) ferrous ammonium sulfate, 500mL Erlenmeyer flask placed under protective effect of carbon dioxide gas stream, Was added 50mL of boiled and cooled water to dissolve, then add 25mL sulfuric acid was added, and the carbon dioxide gas into the sub-surface Flow for protection, quickly and accurately added 35mL potassium dichromate standard titration solution, and then to be calibrated titanium trichloride standard solution titrated to Close to the calculated amount of the end, immediately added 25mL solution of ammonium thiocyanate, and continue to be calibrated with a standard solution of titanium trichloride titration to red Into the green, is the end. Whole titration process should operate under the protection of carbon dioxide gas flow, at the same time make a blank test. B.3.3 Calculation Results Titanium trichloride standard solution...

Tips & Frequently Asked Questions:

Question 1: How long will the true-PDF of GB 4481.2-2010_English be delivered?

Answer: Upon your order, we will start to translate GB 4481.2-2010_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 4481.2-2010_English with my colleagues?

Answer: Yes. The purchased PDF of GB 4481.2-2010_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 [email protected]. 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.

Question 5: Should I purchase the latest version GB 4481.2-2010?

Answer: Yes. Unless special scenarios such as technical constraints or academic study, you should always prioritize to purchase the latest version GB 4481.2-2010 even if the enforcement date is in future. Complying with the latest version means that, by default, it also complies with all the earlier versions, technically.