Directives for the work of standardization--Rules for drafting chemical analysis standards
Some standard content:
National Standard of the People's Republic of China
Guidelines for the work of standardization
Rules For drafting chemical analysis method standards
Dlrectlves for the work of standardizatlonRules For drafting chemical analysis method standardsUDC006
GB 1. 4.-88
This standard adopts the international standard 1S0 78/2---1982 & Standard format - Part 2: Chemical analysis standards. Subject content and scope of application
This standard specifies the general requirements, composition, content and expression form of chemical analysis method standards. This standard is applicable to the compilation of national standards and professional standards (departmental standards) for chemical analysis methods. It should also be used as a reference when compiling local standards and enterprise standards for chemical analysis methods.
2 Reference standards
GB1.1 Guidelines for standardization work Basic provisions for standard preparation GB3102.8 Quantities and units in physical chemistry and molecular physics 3 Basic requirements for chemical analysis method standard preparation 3.1 Basic requirements for chemical analysis method standard preparation should comply with the provisions of chapters 32 of GB1.1. Chemical analysis method standards should be formulated according to the analysis items after the products are properly classified: Generally, they are not formulated separately according to product types or brands:
3.3 If the product being analyzed is hazardous, it should be stated in the scope of application of the analytical method standard, and preventive measures should be written in bold: If the reagents or materials used in milk are hazardous, they should be stated after the reagents or materials in "reagents and materials"; if the analysis steps are hazardous, they should be handled according to 6.7.1.
4 Composition of chemical analysis method standards
The general composition and writing order of chemical analysis method standards are as follows: Cover and capital
Overview
Name of standard
Approved by National Bureau of Standards 1988-04-06 (see Article 5.1)
(See Article 5.2)
(See Article 5.3)
Implementation on December 1, 1988
Title Content Introduction Scope of application
Cited standards
Terms, symbols, codes
Method summary or principle
Reagents and materials
Main text Instruments and equipment
Analysis steps
Expression of analysis results
Precision
Appendix
Supplementary part
Appendix Add explanation
(See 6.1)
(See 6.2)
(See 6.3)
(See 6.4)
(See 6.5)
(See 6.6)
(See 6.7)
(See 6.8)
(See 6.9)
(See 6.10)
(See Chapter 7)
The above components are not exhaustive, nor do any standard need to include all of the above components. When writing a standard, it should be added or omitted according to the situation of its object. 5 Summary
5.1 The cover, first section and table of contents of the chemical analysis method standard shall comply with the provisions of 5.1 to 5.2 in GB 1.1. 5.2 The name of the chemical analysis method standard shall comply with the provisions of Article 5.3 of GB 1.1, and shall also clearly state the product to which the analysis method is applicable, the component or characteristic to be determined, and the nature of the determination method. 5.3 The title of the chemical analysis method standard shall comply with the provisions of Article 5.4 of GB 1.1. 6 Body
6.1 Subject matter and scope of application of chemical analysis method standards The subject matter and scope of application of chemical analysis method standards shall comply with the provisions of Article 6.1 of GB 1.1. Generally, the products to which the method is applicable and the content range of the measured elements (or components) shall be clearly specified. When interference exists, the limits of the interference components shall also be indicated. 6.2 Reference standards and terminology, symbols and codes of chemical analysis method standards The reference standards and terminology, symbols and codes of chemical analysis method standards shall comply with the provisions of Articles 6.2 to 6.3 of GB 1.1. 6.3 Summary or principle of the method
The main steps of the method used and the basic principles adopted shall be briefly described. When necessary, list the main chemical equations and express them as much as possible with ionic reaction formulas.
6. 4 Reagents and Materials
6.4.1 Basic Requirements
6.4.1.1 In analytical methods, unless otherwise specified, only analytically pure reagents and distilled water or water of equivalent purity should be used; basic reagents should be used as reference materials. When making reference materials yourself, the preparation method and specific requirements should be stated. 6.4.1.2 The names of reagents and materials should generally be named according to the systematic naming principles of inorganic and organic chemicals. When its name appears for the first time, its common name or abbreviation can be written in brackets after the name. If necessary, the molecular formula or structural formula should be given after the name. Generally not used Use trade names. In some cases, when trade names are used, the scientific name and molecular formula should generally be indicated. 6.4.1.3 All reagents and materials used in the analytical method should generally be listed with numbers, their basic characteristics such as concentration, density, etc., and the purity specified for use other than analytical grade should be stated. Those used only for preparing reagents are not listed with separate numbers. Generally, the reagent name, grade or standard number and concentration used are written where necessary.
6.4.1.4 When necessary, the precautions for the storage of reagents and materials and the purchase and storage time should be specified, including storage measures, preparation requirements, etc. GB 1. 488
effect phenomenon, etc. For example: prepare it before use and store it in a plastic bottle. If it becomes turbid, it cannot be used. 6.4.1.5 For standard solution: its preparation method should be stated. If necessary, its calibration method should also be written in the batch. If there is a corresponding national standard or professional standard (departmental standard), the standard should be cited. 6.4.1.6 When it is necessary to verify that the reagent does not contain a certain interfering element or purify the reagent, the test details or purification method used for this purpose should be stated. 6.4.1.7 All reagents and materials should be arranged in the following order: Control reagents (excluding blankets): ||tt ||Dissolved or suspended solution (excluding standard titration solution and other standard solutions) and indicate its approximate concentration: Standard titration solution and other standard solutions: d.
Indicator:
Auxiliary materials (desiccant, etc.).
6.41.8 Reagents and materials listed in the analytical method - generally should be listed. In the "analysis steps", the names of the reagents and materials should be written out, and the numbers should be indicated in parentheses. It is not necessary to repeat the characteristics of these reagents and materials. If the reagents and materials are not confused, their names can be written directly without numbers. 6.4.2 Commercial reagents
The characteristics of all listed reagents and materials, such as molecular formula, concentration, etc., should be clearly stated. In particular, for solid reagents containing crystal water, the molecular formula should be written in parentheses after their names. 6.4.3 Liquids
Among the listed reagents and materials, except for solutions with specified solvents, all are aqueous solutions. 6.4.4 Solutions with Determined Concentrations
If the concentration of the prepared solution is determined as a volumetric batch or mass-to-volume ratio, the temperature at which the measurement is made should be given when the concentration significantly affects the accuracy of the measurement:
The definitions and concentration expressions of various solvents are given in Appendix A (Supplementary). 6.4.5 Indicators
Indicators are generally expressed by chemical names such as system names. If possible, they are identified by material index numbers. For example, if the indicator is a liquid, the concentration is expressed in volume percentage when diluted. If the indicator is a solid, the concentration is expressed in grams per liter when the solution is prepared. 6.5 Instruments and Equipment
6.5.1 Specifications of instruments and equipment used in the test (except commonly used instruments) and their main characteristics. 6.5.2 When there are many instruments or equipment listed in the analysis method, the names of the instruments and equipment should generally be written in the "Analysis Steps" and their descriptions should be summarized. It is not necessary to repeat the characteristics of these instruments or equipment to reduce the text description. 6.5.3 If there are corresponding national standards or professional standards (departmental standards) for the instruments or equipment listed in the analysis method, the standards should be quoted. 6.5.4 Special types of instruments or equipment and their components can be described in drawings according to the applicable relevant drawing standards. 6.5.5 When the function of the instrument group is to be verified during the analysis, it should be described in the "calibration test" section of the analysis step. 6.5.6 Special requirements for uncommon instruments or equipment should be stated, especially when these special requirements play an important role in the method or are important factors affecting the reproducibility and accuracy of the method. 6.6 Samples
6.6.1 Definitions
6.6.1.1 Laboratory samples are samples prepared for inspection or testing in the laboratory. 6-6.1.2 Test sample
The sample obtained from the laboratory sample and the test material obtained from it. 6.6.1.3 Test portion
The quantitative sample used for inspection and observation (if the test sample and the laboratory sample are the same, the laboratory sample is weighed). GB 1.4-88
Note: In some cases, "test sample" can also be used to describe the products obtained in the previous steps of the original test step (see 6.7.2.3). 6.6.2 Sampling
In principle, the chemical analysis method standard does not describe the sampling method, but should quote the corresponding chapters and articles of the relevant standards or product standards. If there is no corresponding provision in the current national standards, professional standards (departmental standards), the sampling method can be specified in this article. If necessary, the requirements for the mass or volume, particle size, etc. of laboratory samples, as well as the requirements for storage containers and storage conditions, such as the type, volume, and sealing of storage containers, etc., should also be specified.
6.6.3 Preparation of samples
The samples are prepared from laboratory samples. The steps of sample preparation, such as grinding, reduction, and drying, should be stated, and the characteristics of the prepared samples, such as particle size distribution, approximate mass or volume, etc., as well as the requirements for storage containers and storage conditions, such as the type, capacity, and sealing of storage containers, etc.
6.7 Analysis steps
Each operation step in the analysis should be accurately described in detail, including all necessary pre-operations. If the analysis method used has been found in other standards, it should be expressed as "the method specified in the adoption" or "one of the methods specified in the adoption". If there are any changes to the referenced method, it must be stated.
Analysis steps generally include the following contents: safety measures, test materials, blank test; calibration test, comparison test, determination, and drawing of working curves.
In some cases, other contents that must be specified should also be included, such as the number of repeated measurements, moisture determination, and the use of standard samples. 6.7.1 Safety measures
If there is a risk of explosion, fire or poisoning during the analysis steps, the precautions should be written in cumulative form. If a detailed description of safety measures or first aid methods is required, it can be written in the appendix (reference). B.7.2 Test materials
It should be stated how to remove the test materials from the test sample (or laboratory sample, if the two are the same), what method is used to weigh or extract them, and the mass or volume of the test materials, the precision of weighing, and other relevant characteristics. This item should also state that several test materials are needed to obtain the measurement results. 6.7.2.1 Test materials are expressed in mass
If the test materials are expressed in mass, the weighing method is as follows:. The following expression method is used to weigh a certain amount of sample with a specified accuracy: for example: *m-5.000±0.001g\,
or: "Weigh 5.0008g of sample, accurate to 0.001B" 1b The following expression method is used to weigh an approximate amount of sample with a specified accuracy: for example, "Weigh about 2 g of sample, accurate to 0.001 g". In general, "Weigh the maximum g of sample" means that the mass taken is within ±10% of the specified mass of the sample. If a tolerance smaller than ±10% is required, the following expression method may be used: for example; "Weigh 1.9 to 2.1 samples, accurate to 0.001 g". 6.7.2.2 Samples expressed by volume
If the sample is expressed by a specified volume, the following expression method should be used to indicate the required accuracy of the sample volume to be measured. If an instrument with known precision is required, its accuracy should be stated in the "Instrument and Equipment", for example: 4.1 Pipette: 50 mL, in accordance with GB××××, Class A. Then the identification number of the instrument should be indicated in the "Analysis Steps", for example: "Use a pipette (4.1) to take 10 mL of test solution" b. If the instrument is not specified in advance, the accuracy of the measurement should be stated in the "Analysis Steps", for example, "Take 10.0 mL of test solution", or: "Take 10±0.05 mL of test solution". 6.7.2.3 The sample comes from the previous steps in the analysis step GE 1.4-88
If the sample is the product obtained from the previous steps in the analysis step, such as filtrate, precipitate, residue, etc., its source should be clearly identified in human-written Latin letters.
For example; "Solution A is obtained from the measured filtrate C". 6.7.3 Blank test
The blank test shall be carried out in parallel with the determination using exactly the same analytical steps, reagents and amounts (except for the amount of standard titration solution in the titration method) except that no sample is added.
In case of special circumstances, they shall be clearly stated in this clause. 6.7.4 Calibration test
If it is necessary to pre-check the instrument, such as checking the combustion uniformity in the furnace, or checking the validity of the analytical method with standard samples, synthetic samples or natural products of known purity, all the necessary details of the calibration test shall be specified in this clause. 6.7.5 Comparison test
If it is necessary to reduce or eliminate the interference of certain phenomena (for example, "background" color), an appropriate test method and its analytical steps shall be given in this clause, and the necessary details shall be stated. 6.7.6 Determination
6.7.6.1 The determination operations should be described in sections in the order in which the determination is completed, such as sample decomposition, residue treatment, sedimentation or extraction, weighing or titration, color development and photometric measurement, etc.
6.7.6.2 It must be clearly stated whether the product of a certain operation step (for example, filtrate or precipitate) needs to be retained as the sample for the following steps. If it needs to be retained, it should be numbered with Malaysian Latin letters. When it is needed in subsequent analysis steps, it can be identified according to the letter. For example: "Retain filtrate D for determination". When quoting, "Use filtrate D obtained from the determination". 6.7.7 Preparation of curves
If the analytical method requires the drawing of a working curve, this part needs to be a separate article to write out the detailed steps to be completed. If the detailed steps are completely or partially the same as the aforementioned "determination" operation, it should be stated that it refers to the relevant provisions. For example: "The following is carried out according to steps 1 to 4. ”. 6.8 Expression of analysis results
6.8.1 The method of expressing the results, the calculation formula and simplified formula, the meaning and unit of the symbols, codes and coefficients in the formula, and the number of decimal places required for the analysis results should be stated.
6.8.2 The following letter symbols are used to represent the quantity represented by the calculation formula: For example; AB (lowercase italics) represents mass; V (uppercase italics) represents volume; c (lowercase italics) represents concentration.
When the same letter symbol represents quantities with different values, a footnote should be added to the lower right corner of the letter symbol to distinguish them, for example:, m-, represents masses of different values.
6.8.3 One of the following calculation methods can be used in the titration method: a. In the calculation formula, the symbol c is used to represent the actual concentration of the standard titration solution in moles per liter. At this time, if there is a coefficient, it is the same as 1.00mL of 1.00 mol/L solution: b. If a coefficient is used in the calculation formula and it is exactly equivalent to 1.00mL (in "Reagents and Materials") of a standard titration solution with an accurate concentration, a note should be added: "Note: If the concentration of the standard titration solution used is not exactly the same as the concentration specified in "Reagents and Materials", appropriate corrections should be made."
Example:
Use hydrochloric acid standard titration solution as titrant to determine the alkalinity of a substance. The determined concentration of the hydrochloric acid standard titration solution is 0.200 mol/L. Its mass percentage is expressed as the mass percentage of potassium hydroxide and is given by the following calculation formula: V
GB 1. 4—88
PeX 0. 056 X100
volume of hydrochloric acid standard titration solution (if necessary, give the number in "Reagents and Materials"), mL, -- the actual concentration of hydrochloric acid standard titration solution, tmal/L, m the mass of the sample, B
0. D56 -- the mass of potassium hydroxide equivalent to 1. 00 ml. hydrochloric acid standard titration solution [e(HCI) -1. 00) mol/L], the result should be expressed to two decimal places,
or: VX 0. 011 2 X 100
Where: ... the volume of standard hydrochloric acid titration solution (if necessary, give the number in "Reagents and Materials"), mL; - the mass of the sample:
0. 011 2-
- the mass of potassium hydroxide equivalent to 1.00mL of standard hydrochloric acid titration solution [c(HCI)-0.200ml/L), g. The result should be expressed to two decimal places.
Note: If the concentration obtained by using the standard titration solution is not exactly the same as the concentration specified in "Reagents and Materials", appropriate corrections should be made. 6.9 Precision
The precision of the analytical method (including repeatability and reproducibility) should generally be indicated. The writing of the precision part should comply with the provisions of the relevant standards. When the precision cannot be provided, the allowable error can be specified. 6.10 Others
In addition to the seven technical contents mentioned above, other technical contents can be reasonably written according to the characteristics and requirements of the chemical analysis method, such as instructions for special circumstances, test reports, relevant charts, etc. 7 Supplementary parts
The appendix and additional instructions of the chemical analysis method standard should comply with the provisions of Chapter 6 of GB1.1. GB 1.488
Appendix A
Definition and concentration expression methods of various solutions (consumable parts)
A1 Standard titration solution
standardvolumetricsolution
A1.1 Definition
A solution used for titration analysis to determine the wide range of accurate concentrations. A1.2 Liquidity Expression Method
The concentration of these solutions should be expressed as the amount of substance (in molar concentration [in moles per square meter or moles per liter], the concentration can be expressed as an integer (such as 2ma/m, 1ml/1), or as a decimal (such as 0.06mal/m0.1mol/L). In some cases, the concentration of liquids can also be expressed as a lower mass concentration, such as iridium units can be expressed in grams per liter. The mass or concentration of substance H (symbol ) is defined as: the amount of substance H divided by the volume of the mixture. The SI base unit of amount of substance is the mole, which is defined as follows: The coulometer is the mass of a substance in a system, the base contained in the system. This unit number is equal to the number of atoms in 0.012 dry grams of carbon-12. When using moles, the basic unit should be specified, which can be atoms, molecules, ions, electrons and other particles, or specific combinations of these particles. Therefore, the basic unit must be specified when using the molar concentration of a substance. :
\(NaOH) = 1mol/L is the measurement of a substance equivalent to 1N, that is, 40g of sodium hydroxide per liter. The basic unit is a sodium hydroxide molecule.
(1/2H,S0,) = 3mol)/L is the concentration of a substance equivalent to 3N, that is, 3×49g of sulfuric acid per liter, and the basic unit is half of sulfuric acid.
c(H,S0,) = 1.5mol/L is the molar concentration of a substance equivalent to 3N, that is, 1.5×988 of sulfuric acid per liter, and the basic unit is a sulfuric acid molecule.
e(HS0.)=1mol/L is the concentration of the substance equivalent to 1M or 2N before, that is, 98g of sulfuric acid per liter, and the basic unit is the sulfuric acid molecule.
c(1/5KMn0.)0.1mol/L is the concentration of the substance equivalent to 0.1N before in the case of reaction in an acidic medium. That is, 3.16g of potassium permanganate per liter, and the basic unit is the fraction of potassium permanganate. HgCl2 = 1mol/L is the concentration of the substance equivalent to 1N, that is, each liter contains 236.0-1g of mercury chloride, and the basic unit is one part of the mercury molecule. HgCl2 = 1mol/L is the concentration of the substance equivalent to 1M or 2N, that is, each liter contains 472.0g of mercury chloride. The basic unit is mercury chloride molecule. HgCl2 = 1mol/L is the concentration of the substance equivalent to 1M or 2N, that is, each liter contains 401.18g of mercury chloride. The basic unit is 1
c(1/2Ca)=1mo1/L is equivalent to the molar concentration of 1N, that is, there are 20.01 calcium cations per liter. The basic unit is half of the calcium cation.
Note: In contrast, the technical spectrum used in this paper is the current (or specified) concentration (symbol N) and the molar (or gram) concentration (symbol M). The corresponding expression method is as described above, the molar (or gram molecule) concentration (symbol M> is not required for the standard solution A2 standard tefetence Nolution A2. 1 Definition
Solutions prepared from reference substances or calibrated by various methods, used to calibrate other solutions. A2.2 Method of expressing concentration
The concentrations of these solutions shall be expressed in the same manner as described for standard solutions (see A1.2). A3 Standard solution
A3.1 Definition
Solutions whose concentrations of certain elements, ions, compounds or groups are accurately known from the substances used to prepare the solutions. A3.2 Method of expressing concentration
The concentrations of these solutions shall be expressed in grams per litre or in multiples thereof. A4 Standard matching solution Note: 1) This term is only used as a general term for these solutions. Each of these solutions shall be more accurately defined by appropriate adjectives, for example: "standard matching solution", "standard matching solution". A4.1 Definition
Solutions whose relevant properties (such as color, colorimetry) are accurately known or specified, used to evaluate test solutions related to these properties. It can be prepared from solutions of A1, A2, A3 or other solutions with the required properties. Note: The method of preparing the standard solution should usually be given in the "Drawing of the Concentration Line" (see 6.7.7). A4.2 Method of expressing concentration
The concentration of such solutions should be expressed in the same way as described in A1.2, A2.2 or A3.2. A5 Other solutions
A5, 1 If the concentration of a solution is given on the basis of mass ratio or volume ratio, it can be expressed as a percentage in the following ways: *% (m/m) or --% (V/V).
5.2 If the concentration is expressed in mass and volume units with different dimensions, the concentration should be expressed in grams per liter or its appropriate multiple. A5, 3 If a solution is prepared by diluting another specific solution, it should be expressed according to the following convention: "Dilution → V" means that a specific solution with a volume of V is diluted in a certain way, and the total volume of the final mixture is V! b. *Dilution V,+V,\ means adding a specific solution with a volume of V to a solvent with a volume of V,. Additional remarks:
This standard was drafted by the China National Institute of Standardization.16g, the basic unit is the molar mass of potassium permanganate. HgCl2 (HgCl2) = 1mol/L is the concentration of the substance equivalent to 1N, that is, each liter contains 236.0-1g of mercury chloride, the basic unit is one part of mercury molecule. HgCl2 (HgCl2) = 1mol/L is the concentration of the substance equivalent to 1M or 2N, that is, each liter contains 472.0g of mercury chloride. The basic unit is mercury chloride molecule. Hg (Hg) = 1mol/L is the concentration of the substance equivalent to 1M or 2N, that is, each liter contains 401.18g of mercury chloride. The basic unit is 1
c(1/2Ca)=1mo1/L is equivalent to the molar concentration of 1N, that is, there are 20.01 calcium cations per liter. The basic unit is half of the calcium cation.
Note: In contrast, the technical spectrum used in this paper is the current (or specified) concentration (symbol N) and the molar (or gram) concentration (symbol M). The corresponding expression method is as described above, the molar (or gram molecule) concentration (symbol M> is not required for the standard solution A2 standard tefetence Nolution A2. 1 Definition
Solutions prepared from reference substances or calibrated by various methods, used to calibrate other solutions. A2.2 Method of expressing concentration
The concentrations of these solutions shall be expressed in the same manner as described for standard solutions (see A1.2). A3 Standard solution
A3.1 Definition
Solutions whose concentrations of certain elements, ions, compounds or groups are accurately known from the substances used to prepare the solutions. A3.2 Method of expressing concentration
The concentrations of these solutions shall be expressed in grams per litre or in multiples thereof. A4 Standard matching solution Note: 1) This term is only used as a general term for these solutions. Each of these solutions shall be more accurately defined by appropriate adjectives, for example: "standard matching solution", "standard matching solution". A4.1 Definition
Solutions whose relevant properties (such as color, colorimetry) are accurately known or specified, used to evaluate test solutions related to these properties. It can be prepared from solutions of A1, A2, A3 or other solutions with the required properties. Note: The method of preparing the standard solution should usually be given in the "Drawing of the Concentration Line" (see 6.7.7). A4.2 Method of expressing concentration
The concentration of such solutions should be expressed in the same way as described in A1.2, A2.2 or A3.2. A5 Other solutions bzxZ.net
A5, 1 If the concentration of a solution is given on the basis of mass ratio or volume ratio, it can be expressed as a percentage in the following ways: *% (m/m) or --% (V/V).
5.2 If the concentration is expressed in mass and volume units with different dimensions, the concentration should be expressed in grams per liter or its appropriate multiple. A5, 3 If a solution is prepared by diluting another specific solution, it should be expressed according to the following convention: "Dilution → V" means that a specific solution with a volume of V is diluted in a certain way, and the total volume of the final mixture is V! b. *Dilution V,+V,\ means adding a specific solution with a volume of V to a solvent with a volume of V,. Additional remarks:
This standard was drafted by the China National Institute of Standardization.16g, the basic unit is the molar mass of potassium permanganate. HgCl2 (HgCl2) = 1mol/L is the concentration of the substance equivalent to 1N, that is, each liter contains 236.0-1g of mercury chloride, the basic unit is one part of mercury molecule. HgCl2 (HgCl2) = 1mol/L is the concentration of the substance equivalent to 1M or 2N, that is, each liter contains 472.0g of mercury chloride. The basic unit is mercury chloride molecule. Hg (Hg) = 1mol/L is the concentration of the substance equivalent to 1M or 2N, that is, each liter contains 401.18g of mercury chloride. The basic unit is 1
c(1/2Ca)=1mo1/L is equivalent to the molar concentration of 1N, that is, there are 20.01 calcium cations per liter. The basic unit is half of the calcium cation.
Note: In contrast, the technical spectrum used in this paper is the current (or specified) concentration (symbol N) and the molar (or gram) concentration (symbol M). The corresponding expression method is as described above, the molar (or gram molecule) concentration (symbol M> is not required for the standard solution A2 standard tefetence Nolution A2. 1 Definition
Solutions prepared from reference substances or calibrated by various methods, used to calibrate other solutions. A2.2 Method of expressing concentration
The concentrations of these solutions shall be expressed in the same manner as described for standard solutions (see A1.2). A3 Standard solution
A3.1 Definition
Solutions whose concentrations of certain elements, ions, compounds or groups are accurately known from the substances used to prepare the solutions. A3.2 Method of expressing concentration
The concentrations of these solutions shall be expressed in grams per litre or in multiples thereof. A4 Standard matching solution Note: 1) This term is only used as a general term for these solutions. Each of these solutions shall be more accurately defined by appropriate adjectives, for example: "standard matching solution", "standard matching solution". A4.1 Definition
Solutions whose relevant properties (such as color, colorimetry) are accurately known or specified, used to evaluate test solutions related to these properties. It can be prepared from solutions of A1, A2, A3 or other solutions with the required properties. Note: The method of preparing the standard solution should usually be given in the "Drawing of the Concentration Line" (see 6.7.7). A4.2 Method of expressing concentration
The concentration of such solutions should be expressed in the same way as described in A1.2, A2.2 or A3.2. A5 Other solutions
A5, 1 If the concentration of a solution is given on the basis of mass ratio or volume ratio, it can be expressed as a percentage in the following ways: *% (m/m) or --% (V/V).
5.2 If the concentration is expressed in mass and volume units with different dimensions, the concentration should be expressed in grams per liter or its appropriate multiple. A5, 3 If a solution is prepared by diluting another specific solution, it should be expressed according to the following convention: "Dilution → V" means that a specific solution with a volume of V is diluted in a certain way, and the total volume of the final mixture is V! b. *Dilution V,+V,\ means adding a specific solution with a volume of V to a solvent with a volume of V,. Additional remarks:
This standard was drafted by the China National Institute of Standardization.
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