What is the difference between sulfuric acid and dilute sulfuric acid, sulfuric acid and dilute sulf

The chemical equation is exactly the same.

But there is a difference in chemical properties. Concentrated sulfuric acid has stronger oxidizing properties than dilute sulfuric acid. For example, copper cannot react with dilute sulfuric acid, but copper can react with concentrated sulfuric acid under heated conditions.

Concentrated sulfuric acid can be used to convert certain metals, such as iron and copper. Concentrated sulfuric acid reacts with metals to give hydrogen gas.

To put it simply, the dehydration, water absorption, and strong oxidation of concentrated sulfuric acid are different from those of dilute sulfuric acid.

The above is just the "tip of the iceberg", because there is so much to say...

The chemical formula is the same, but concentrated sulfuric acid has strong oxidizing properties, and when it reacts with organic matter, it will be dehydrated, for example, if you put concentrated sulfuric acid in wood, it will turn black, but dilute acid does not have this property.

Concentrated sulfuric acid also has water absorption, it contains only a small amount of water, and it cannot be written as an ionic formula in middle school chemistry, and it must be sealed and preserved, which is different from dilute acid.

Dilute sulfuric acid is a kind of sulfuric acid including concentrated sulfuric acid, concentrated sulfuric acid is sulfuric acid with very low water content, strong sulfuric acid has strong oxidation, adding water will produce heat, so if the dilution of concentrated sulfuric acid is too fast, it will cause **, so be careful, and dilute sulfuric acid will not produce heat, concentrated sulfuric acid can be packed in an iron cylinder, because concentrated sulfuric acid can produce an oxide film on the surface of iron, and will not react with iron, and dilute can not be packed in an iron cylinder, which will produce chemical reaction and produce hydrogen.

1. The oxidation is different.

Concentrated sulfuric acid has strong oxidation reflected in S, and dilute sulfuric acid has weak oxidation reflected in hydrogen ions.

2. The concentration is different.

The concentration of concentrated sulfuric acid is very large, and it is difficult to change from dilute sulfuric acid to concentrated sulfuric acid by evaporating water alone. Therefore, in industry, dilute sulfuric acid is heated, concentrated, and fractionated to continuously produce industrial 98 sulfuric acid or 92 5 sulfuric acid, and distillation to produce battery sulfuric acid.

3. Different dehydration.

Dehydration is the property of concentrated sulfuric acid, not dilute sulfuric acid, that is, concentrated sulfuric acid is dehydrated and very dehydrated. Dilute sulfuric acid is not dehydrating.

The properties of dilute sulfuric acid are very similar to hydrochloric acid, which can make the purple litmus solution turn red, make the green bromothymol blue solution yellow, react with the active metal before hydrogen to release hydrogen, and react with alkalis and alkaline oxides to form salt and water, and can also react with salt, if it reacts with barium chloride solution or barium nitrate solution, it will generate a white barium sulfate precipitate that is insoluble in dilute hydrochloric acid or dilute nitric acid.

Pure sulfuric acid is colorless, viscous oily liquid, not easy to volatile, its density is 1840 kilograms of cubic meters, it reacts with metal, it will oxidize the metal into metal oxide, and then react with excess sulfuric acid to form sulfate, sulfuric acid itself will be reduced to sulfurous acid, and then decomposed into sulfur dioxide and water.

Concentrated sulfuric acid can also remove hydrogen atoms and oxygen atoms from organic compounds in a ratio of 2:1 (the composition ratio of water), which is the dehydration of concentrated sulfuric acid. Laboratory-made ethylene or carbon monoxide is the dehydration of concentrated sulfuric acid.

When concentrated sulfuric acid is dissolved in water, a large amount of heat is released, so when diluting concentrated sulfuric acid, it is necessary to sell concentrated sulfuric acid along the wall of the container and slowly inject it into the water, and constantly stir it, so that the generated heat spreads rapidly, and the water temperature rises slowly.

Concentrated sulfuric acid can also directly absorb water vapor in the air, which is the water absorption of concentrated or hall sulfuric acid, we often use concentrated sulfuric acid as a desiccant, which can be used with hidden drying hydrogen, oxygen, carbon dioxide and other gases, but can not dry reducing or alkaline gases.

Cu + 2H2SO4 (concentrated) Heating = CuSo4 + SO2 + 2H2O. The phenomenon of this reaction is that the copper is gradually dissolved, bubbles are formed, and the resulting gas can cause the purple litmus to turn red or the magenta solution to fade. Pure sulfuric acid is a colorless and odorless oily liquid with a high boiling point and difficult to volatile, soluble in water, and a strong acid.

It is highly corrosive.

The first case: excess concentrated sulfuric acid. According to the course of the experiment, the phenomena that can be observed are as follows:

Copper and cold concentrated sulfuric acid do not have a slippery reaction, and there is no phenomenon at the beginning of the reaction; After heating, with the increase of system temperature, the surface of the copper wire (or copper sheet) turns black, producing colorless gas, and fine black granular matter enters the concentrated sulfuric acid from the surface of the copper wire (or copper sheet) to form a black suspension; Continue to heat until boiling, the granular matter changes from black to gray-white, and a large amount of white smoke is produced in the test tube; Some of the smoke condenses at the inner wall of the upper part of the test tube to form a yellowish solid substance, which eventually disappears after continuous heating of concentrated sulfuric acid (boiling). The exported gas can cause the purple litmus solution to turn red, and the magenta solution and KMNO4 solution to fade. After all the copper is reacted, the heating is stopped, and after standing, the smoke in the test tube slowly disappears, the liquid in the test tube is light blue, and the solid matter deposited at the bottom of the tube is gray-white.

Continue to cool the tube, the color of the solution slowly becomes lighter, and it is almost colorless at room temperature; This colorless solution is injected into a test tube containing a small amount of water, and the resulting solution turns light blue.

Differences: different concentrations and densities.

The concentration of concentrated sulfuric acid is higher than that of dilute sulfuric acid. Concentrated sulfuric acid has a high density, and the same volume of concentrated sulfuric acid and dilute sulfuric acid, the mass of concentrated sulfuric acid is large.

Sulfuric acid (chemical formula: H2SO4), the most important oxygenated acid of sulfur. Anhydrous sulfuric acid is a slag-free oily liquid, when crystallized, it is usually used in various concentrations of aqueous solutions, using tower method and contact method.

Sulfuric acid is one of the most reactive binary inorganic acids that reacts with most metals. High concentration of sulfuric acid has strong water absorption, can be used as a dehydrating agent, carbonized wood, paper, cotton and linen fabrics and biological skin and other carbohydrate-containing substances. When mixed with water, a large amount of heat energy is also emitted.

It is highly corrosive and oxidizing, so it should be used with caution. It is an important industrial raw material, which can be used to make fertilizers, medicines, explosives, pigments, detergents, batteries, etc., and is also widely used in purifying petroleum, metal smelting to evoke the New Year and dyes and other industries. It is often used as a chemical reagent and can be used as a dehydrating agent and sulfonating agent in organic synthesis.

Concentrated sulfuric acid, commonly known as bad water, with the chemical formula H SO, is a strong mineral acid with high corrosiveness. Concentrated sulfuric acid refers to a solution of sulfuric acid with a mass fraction greater than or equal to 70%. Concentrated sulfuric acid has strong oxidizing properties at high concentrations, which is one of the biggest differences between it and dilute sulfuric acid.

At the same time, it also has dehydration, strong corrosiveness, refractory volatile, acidic, water absorption, etc.

Dilute sulfuric acid refers to the aqueous solution of sulfuric acid with solute mass fraction less than or equal to 70%, because the sulfuric acid molecules in dilute sulfuric acid have been completely ionized, so dilute sulfuric acid does not have the strong oxidation, water absorption, dehydration (commonly known as carbonization, that is, strong corrosiveness) and other special chemical properties of concentrated sulfuric acid.

The difference is very large, concentrated sulfuric acid is dense, viscous, very corrosive, oxidizing, absorbent and dehydrated, soluble in water and heats up a lot. Dilute sulfuric acid is generally hydrogen ions that are oxidizing and react with metal elements, reducing corrosiveness.

Sulfur trioxide is dissolved in water to form sulfuric acid, the concentration is below 70%, there are hydrogen ions and sulfate ions in the solution, the dissolution is acidic, it has the characteristics of acid, and the metal in front of the metal in the wide pH test paper is red and the metal activity table hydrogen is replaced by the reaction, which is usually called dilute sulfuric acid.

Sulfur trioxide continues to dissolve the solution and the concentration can reach more than 98%, and it is called concentrated sulfuric acid when it is greater than 70%. It can also continue to dissolve sulfur trioxide to 105% (called oleum). At this time, the solution has a strong 1, water absorption (water absorption) and can be used as a local air desiccant.

2. It has dehydration (the hydrogen and oxygen ions in the organic matter in contact with it are absorbed into water molecules) to carbonize the organic matter. 3. It has oxidizing properties (the sulfuric acid molecules in concentrated sulfuric acid are decomposed into water and sulfur trioxide, and the form is decomposed into sulfur dioxide and oxygen in one step), and the decomposed oxygen has a strong oxidizing effect.

Therefore, people who come into contact with concentrated sulfuric acid clothes and people's ** will be dehydrated and coking!