2How does sulfur oxide become sulfuric acid, and how does sulfur dioxide react with sulfuric acid?

The industrial contact method of sulfuric acid is first catalyzed by the catalyst vanadium pentoxide V2O5 and reacts with oxygen to form sulfur trioxide, and then reacts with water in concentrated sulfuric acid to produce sulfuric acid.

2so2+o2===(v2o5)2so3

so3+h2o===h2so4

The process of acid rain in the atmosphere is that sulfur dioxide is first dissolved in water to form sulfurous acid (to achieve chemical equilibrium and dissolution equilibrium), and sulfurous acid is oxidized by oxygen in the air to form sulfuric acid.

The reaction process of industry is different from that of acid rain, largely because of the different requirements for the rate and yield of the reaction. The rate of formation of sulfuric acid in the atmosphere is relatively low, and the final acid rain is also a mixed solution of sulfuric acid and sulfurous acid. Economical requirements in industry.

In addition, some dust in the air exists in water after becoming a condensation nucleus of water vapor, which also plays a certain role in catalyzing sulfur dioxide oxidation.

First, it reacts with water vapor in the air to form sulfurous acid, and then the sulfurous acid is oxidized by oxygen in the air to form sulfuric acid and form acid rain

Acid rain in the atmosphere is formed by the process of sulfur dioxide being dissolved in water to form sulfurous acid, which is then oxidized by oxygen in the air to form sulfuric acid. Sulfuric acid mixes with rainwater and falls to the ground, which is called acid rain.

First, it reacts with oxygen under the catalysis of a catalyst to form sulfur trioxide, and then reacts with water to form sulfuric acid.

2SO2+O2=== (catalyst) 2SO3

so3+h2o===h2so4

Industrially, 98% concentrated sulfuric acid is used to absorb sulfur trioxide and improve purity.

Sulfur trioxide first, then sulfuric acid.

Sulfur dioxide and dilute sulfuric acid are not reactive, but when sulfur dioxide is introduced into dilute sulfuric acid, sulfur dioxide will have a small amount (very little) of sulfurous acid with water to form sulfurous acid, equation: SO2 + H2O = H2SO3.

Pure sulfuric acid is generally a colorless oily liquid with a density of g cm and a boiling point of 337, which can be miscible with water in any proportion, and at the same time release a large amount of heat to make the water boil. When heated to 290, sulfur trioxide is released, and finally becomes an aqueous solution, which boils at 317 and becomes an azeotropic mixture.

The high boiling point and viscosity of sulfuric acid are due to the strong hydrogen bonds inside its molecules. Due to the higher dielectric constant of sulfuric acid, it is a good solvent for electrolytes, whereas solvents as a non-electrolyte are less ideal. The melting point of sulfuric acid is that the freezing point will decrease when added to water or sulfur trioxide.

Areas of application of sulfuric acid:

Sulfuric acid is used in the production of petroleum products such as gasoline and lubricating oil in the petroleum industry, and concentrated sulfuric acid is required to refine to remove sulfur-containing compounds and unsaturated hydrocarbons. About 24kg of sulfuric acid is required for refining per ton** and about 31kg of sulfuric acid is required for refining per ton of diesel. The preparation of activated clay used in the petroleum industry also consumes a lot of sulfuric acid.

Sulfuric acid is used in the dye industry, and there is hardly a dye (or its intermediate) that is prepared without the use of sulfuric acid. The preparation of azo dye intermediates requires sulfonation, and the preparation of aniline dye intermediates requires nitrification, both of which require the use of large amounts of concentrated sulfuric acid or oleum. Therefore, some dye factories have sulfuric acid workshops to meet the needs.

The above content reference: Encyclopedia - sulfuric acid.

Concentrated sulfuric acid and sulfur dioxide cannot react.

There is no stable intermediate valence of sulfur dioxide and sulfuric acid, so sulfur dioxide will not be oxidized by sulfuric acid to sulfuric acid, and sulfuric acid will not be reduced to sulfur dioxide by sulfur dioxide.

Redox reaction is a type of reaction in which the oxidation number of an element changes before and after a chemical reaction. The essence of a redox reaction is the gain or loss of electrons or the shift of shared electron pairs.

Concentrated sulfuric acid precautions.

Leak handling. Quickly evacuate the personnel in the leakage contaminated area to a safe area, isolate them, and strictly restrict access to them. It is recommended that emergency responders wear self-contained positive pressure respirators and anti-acid and alkali overalls.

Do not come into direct contact with spills. Cut off the source of the leak as much as possible. Prevent the flow into restricted spaces such as sewers and drainage ditches.

Small leaks: Mix with sand, dry lime or soda ash. It can also be rinsed with a large amount of water, diluted with washing water and put into the wastewater system.

Massive leakage: Construct embankments or dig pits to contain them. Transfer by pump to a tanker or special collector** or transport to a waste disposal site.

If the concentration of sulfuric acid is different, the method of reaction to form sulfur dioxide is different. Therefore, according to the concentration of sulfuric acid, there are two ways to turn sulfuric acid into sulfur dioxide:

1. At room temperature, dilute sulfuric acid and sodium sulfite solution are reacted, and the products of the chemical reaction are: sulfur dioxide, sodium sulfite and water;

2. Under the condition of heating, the concentrated sulfuric acid of Liangyun and the inactive metal are bonded together, such as Cu or Ag, etc., and the products of the chemical reaction are: sulfur dioxide, sulfate corresponding to the inactive metal cavity and water.

Sulfur dioxide is converted to sulfur trioxide, that is, positive 4 becomes positive 6 valence, which requires an oxidant to oxidize.

The sulfur dioxide production method in the laboratory uses sodium sulfite and concentrated sulfuric acid to react to produce sulfur dioxide, or uses copper and concentrated sulfuric acid to heat sulfur dioxide, and sulfur dioxide should be obtained from the reverse number.

At the end of the experiment, sodium hydroxide solution 2NaOH+SO=NaSO+HO.

Note that because so is easily soluble in water, the concentrated H so and Na SO(S) reactions should be selected, the reaction is between solid and liquid, and Na SO(S) is in powder form, in order to control the reaction rate, the concentrated H so should be dropped drop by drop from the separating funnel.

Concentrated hydrochloric acid cannot be used, because it contains a large amount of water (at room temperature and pressure, the largest concentrated hydrochloric acid with the largest mass fraction is 45% concentrated hydrochloric acid), otherwise there will be a large amount of SO (dissolved in water.

The concentrated H SO (i.e., the concentrated H SO with a mass fraction of 98%) cannot be used, because there is a lack of water in it, and the sulfuric acid is not ionized, and it still exists in molecular form.

However, the reaction between Na SO (S) and H So can only be carried out smoothly in the state of ionization of H SO, so a concentrated H SO with a volume ratio of 1 1 is usually used

Extended Information: Main Uses of Sulphur Dioxide.

Clause. 1. Preservative, due to the antibacterial properties of sulfur dioxide, it is sometimes used as a preservative for dried apricots and other dried fruits, to maintain the appearance of fruits, and to prevent rot.

Clause. 2. Sulfur dioxide is a very useful compound when making wine, it acts as an antibiotic and antioxidant to prevent wine from being damaged and oxidized by bacteria. It also helps to keep the volatile acidity at the desired level.

Clause. 3. Reducing bleach, sulfur dioxide is still a good reducing agent. In the presence of water, sulfur dioxide can fade the substance.

In particular, it is a useful bleach for paper and clothing. This bleaching effect usually doesn't last long. Oxygen in the air re-oxidizes the reduced dye and restores its color.

Clause. Fourth, the precursor of sulfuric acid, sulfur dioxide is also used to prepare sulfuric acid, which is first converted into sulfur trioxide, then converted into oleum sulfuric acid, and finally converted into sulfuric acid.

The absorption of sulfur trioxide is caused by the sulfate in it. When sulfate is dissolved in water, it will be hydrolyzed into sulfate and sulfate, which will be dissolved with the flow of water, respectively, H2SO4 and will be dissolved with the flow of water. When the sulfate is dissolved by H2S, it will react to produce S and Hs, S will be absorbed and Hs will be released.

The reaction mechanism is caused by the reaction between H2S and H2SO4, and the last reaction that occurs is: H2S + H2SO4 2S + 2H2O. As a result of this reaction, sulfur trioxide is absorbed and does not become sulfur dioxide.

Sulphur trioxide is completely absorbed in the reaction, and no remaining sulphur trioxide is emitted, and it does not become sulphur dioxide. The absorption reaction of sulfur oxide containing three mu can also be caused by potassium sulfate, which refers to the hydrolysis of sulfate H2SO4 into H2S and will be dissolved, while K2SO4 will be precipitated out. The mechanism of the reaction is a reaction between H2S and H2SO4, and the final product produced is 2S + 2K2SO4, which is also the sulfur trioxide that is completely absorbed without turning into sulfur dioxide.

As can be seen from the above, sulfur trioxide does not turn into sulfur dioxide, whether it is an absorption reaction caused by sulfate or a reaction caused by potassium sulfate. They will be completely absorbed without any remaining sulfur trioxide being emitted, so sulfuric acid absorption will not turn sulfur trioxide into sulfur dioxide.

Sulfur trioxide can be decomposed by heat to obtain sulfur dioxide and take guess with oxygen!

It's like the reaction of sulfur dioxide and oxygen to get trillions of oxygen and sulfur!

Because they are reversible reactions!

2SO2 + O2 = 3SO3 (this is a reversible reaction, so the reversible symbol should be used in the middle).

Sulfur dioxide and oxygen are heated under the catalytic conditions of vanadium pentoxide to produce sulfur trioxide.

Sulphur dioxide: is the most common and simple sulphur oxide. One of the main pollutants in the atmosphere, the gas is ejected during volcanic eruptions, and sulfur dioxide is produced during industrial production.

Sulfur trioxide: It is a colorless and easily sublimated solid, with three phases, which is a liquid in normal cases, a solid in the standard case, and a gas after heating.

Vanadium pentoxide: widely used in metallurgy, chemical and other industries, mainly used for smelting ferrovanadium, used as an alloy additive, and secondly, used as a catalyst for organic chemicals.