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Anonymous users2024-02-071. Take the solution that is less than the amount of the test in the test tube;
2. Drop 2 to 3 drops of purple litmus solution, if the solution turns red, it proves that it contains hydrogen ions, and it is concluded that it is acid;
3. Take a small amount of the tested solution and add barium nitrate or barium hydroxide to the test tube, if the white precipitate is produced, dilute nitric acid is added, and the white precipitate does not disappear, which proves that it contains sulfate ions. Based on the above, it can be proved that it is sulfuric acid.
Sulfuric acid is one of the three major inorganic strong acids in chemistry, and it is a colorless and odorless oily liquid. The mass fraction of H2SO4 in the commonly used concentrated sulfuric acid is 1, its density is 1, 84g per cubic centimeter, and the concentration of its substance is moles per liter. Sulfuric acid is a strong acid with a high boiling point and difficult to volatilize, which is soluble in water and can be miscible with water in any ratio.
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Anonymous users2024-02-061. Take a small amount of the solution to be tested in the test tube;
2. Drop 2 to 3 drops of purple litmus solution, if the solution turns red, it proves that it contains hydrogen ions, and it is concluded that it is acid;
3. Take a small amount of the solution that has been tested by the test and add barium nitrate or barium hydroxide to the test tube, if the white precipitate is produced, then add dilute nitric acid, and the white precipitate does not disappear, which proves that it contains sulfate ions. Based on the above, it can be proved that it is sulfuric acid.
Sulfuric acid is one of the three major inorganic strong acids in chemistry, and it is a colorless and odorless oily liquid. The mass fraction of H2SO4 in the commonly used concentrated sulfuric acid is , its density is g per cubic centimeter , and the concentration of its substance is moles per liter. Sulfuric acid is a strong acid that is resistant to high boiling point and difficult to volatile, soluble in water, and can be miscible with water in any ratio.
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Anonymous users2024-02-05The spike macro determination methods for sulfuric acid content include pH test paper and purple litmus method.
Test strip method. Take a small piece of test paper on the surface dish or glass plate, dip the liquid to be tested with a clean and dry glass rod and drop it in the middle of the test paper, observe the color after the change is stable, compare it with the standard color card, judge the nature of the solution, dip the liquid with a clean glass rod, and drop it into the purple litmus test solution.
1) If the test solution is red, it means that the liquid is acidic;
2) If the test solution is blue, it means that the liquid is alkaline; 3.If it is purple, it is neutral, and if the red index of sulfuric acid is very high, it means that the concentration of sulfuric acid is very high.
2.Purple litmus method.
Commodity litmus is powdered blue, lumpy, or pressed into squares. Its main chemical components are C9H10O5N and C13H22O6. Commercially available litmus contains many fillers, only 4% 5% of the active ingredient, the acid solution turns red, the excess alkali solution turns blue again, and the pH change range is between 5 and 8.
If the red index of sulfuric acid is very high, it means that the concentration of sulfuric acid is very high.
Uses of Sulfuric Acid:
1. It can be used as a softener, ion exchange regenerator, pH adjuster, oxidant and detergent for hard water. It can also be used in the manufacture of fertilizers, pesticides, dyes, pigments, plastics, chemical fibers, explosives and various sulfates.
It is widely used in petroleum refining, non-ferrous metal smelting, iron and steel pickling, tanning process, coking industry, light textile industry, and national defense and military industry. Strong acidic cleaning corrosives. It is mainly used for silicon wafer cleaning in the integrated circuit manufacturing process.
2. For the production of daily necessities, oleum sulfuric acid and concentrated sulfuric acid are required for the production of synthetic detergents. Plasticizers for plastics (such as phthalic anhydride and phthalates) and nitrocellulose wool, the raw material for celluloid products, all need sulfuric acid to prepare for neutralization. Sulfuric acid is also used in the manufacture of cellophane and parchment paper.
In addition, the textile printing and dyeing industry, enamel industry, small hardware industry, soap industry, artificial fragrance industry and other production sectors also need to use sulfuric acid. <>
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Anonymous users2024-02-04The difference between oleum and 98% sulfuric acid is that 98% sulfuric acid generally has water in it, and oleum sulfuric acid uses sulfuric acid as a solvent to absorb sulfur trioxide. There are two types of sulfuric acid that are commonly found between 90-98, and the most common ones are 25% and 65%.
oleum and sulphuric acidFeatures:
Sulfuric acid solution of sulfur trioxide. The density, melting point, and boiling point of colorless to light brown viscous fuming liquid vary depending on the SO3 content. When it is exposed to the air, the volatilized SO3 and the water vapor in the air form fine dew droplets of sulfuric acid and smoke, so it is called oleum acid.
Oleum can be seen as sulfuric acid with a concentration of more than 98%.
Sulfuric acid is a colorless and odorless oily liquid, a strong acid with a high boiling point and difficult to volatilize, soluble in water, and can be miscible with water in any ratio to be configured into a sulfuric acid solution of different concentrations, and this sulfuric acid solution is also commonly called Xuming sulfuric acid.
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Anonymous users2024-02-03Legal analysis: the national standard for industrial sulfuric acid mainly includes two aspects: first, the technical requirements of industrial sulfuric acid; The second is the inspection method of industrial sulfuric acid.
Legal basis: Standardization Law of the People's Republic of China
Article 2 The term "standards" (including standard samples) as used in this Law refers to the technical requirements that need to be unified in the fields of agriculture, industry, service industry, and social undertakings.
Standards include national standards, industry standards, local standards, group standards, and enterprise standards. National standards are divided into mandatory standards and recommended standards, and industry standards and local standards are recommended standards.
Mandatory standards must be enforced. The State encourages the adoption of recommended standards.
Article 3 The task of standardization work is to formulate standards, organize the implementation of standards, and supervise the formulation and implementation of standards.
The people at or above the county level shall incorporate the standardization work into the national economic and social development plan at the same level, and include the standardization work funds in the budget at the same level.
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