Fade acidic potassium permanganate, what can fade potassium permanganate

Potassium permanganate is reduced to low-cost manganese ions by a redox reaction, which fades.

In an acidic solution, potassium permanganate is oxidizing and reacts with reducing substances to form divalent manganese ions, which fade the color of potassium permanganate.

Acidic potassium permanganate is a strong oxidizing agent, as long as there are reducing substances can make it fade, the common are: ferrous ions, ethylene, acetaldehyde, hydrogen peroxide, sulfur dioxide, hydrogen sulfide, ammonia, nitrogen dioxide, etc.

Common reducing agents are acceptable.

In organic matter, when the molecule contains structure, unsaturated bonds between carbon atoms (except benzene ring), primary alcohols (such as ethanol), aldehyde groups (formaldehyde, acetaldehyde, formic acid), reducing aromatic compounds (phenol, aniline), other benzene homologues and derivatives (such as toluene, xylene, salicylic acid), etc., can fade the acidic potassium permanganate.

There are also many common reducing substances in inorganic substances, such as hydrogen sulfide, sulfur dioxide, alkali metal +3 cr, iodide ions, etc., and among the common reducing agents, there are hydrogen and carbon monoxide that cannot fade the acidic potassium permanganate.

By the way, if the acidic potassium permanganate solution is relatively concentrated, it will also gradually fade during the placement process, and the water is oxidized by the acidic potassium permanganate as a reducing agent.

Reducing agents are used, generally oxalic acid.

In organic matter, when the molecule contains structure.

Olefins, alkynes, primary alcohols, secondary alcohols, aldehydes, formic acid, phenols, aniline, ......

The substances that can make potassium permanganate fade are: organic substances, inorganic substances, unsaturated substances and their derivatives.

1. Organic substances that fade the acidic potassium permanganate solution:

Unsaturated hydrocarbons (olefins, alkynes, diolefins, styrene, etc.), benzene homologues, derivatives of unsaturated hydrocarbons (enols, enal, oleic acids, halogenated hydrocarbons, oleic acid, oleates, oleates, etc.), aldehyde-containing organic compounds (aldehydes, formic acid, formate, formate, etc.), petroleum products (pyrolysis gas, cracking gas, pyrogasoline, etc.), coal products (coal tar), natural rubber (polyisoprene).

2. Inorganic substances that can fade the acidic potassium permanganate solution

2-valent sulfur compounds (H2S, hydrosulfuric acid, sulfides), +4-valent sulfur compounds (SO2, H2SO3 and sulphites), hydrogen peroxide (H2O2, where oxygen is -1 valence).

3. Unsaturated substances and their derivatives that fade acidic potassium permanganate:

Reaction with unsaturated hydrocarbons such as olefins, alkynes, and diolefins to fade potassium permanganate solution, reaction with benzene homologues (toluene, ethylbenzene, xylene, etc.) to fade the acidic potassium permanganate solution, redox reaction with phenol to fade potassium permanganate solution, redox reaction with aldehydes and other aldehyde groups, discoloration of potassium permanganate solution, and reaction with reducing inorganic reducing agent to fade potassium permanganate solution.

1. Fade the acidic potassium permanganate solution to the organic substance1. Unsaturated hydrocarbons (olefins, alkynes, diolefins, styrene, etc.);

2. Homologues of benzene;

3. Derivatives of unsaturated hydrocarbons (enols, enal, oleic acids, halogenated hydrocarbons, oleic acid, oleates, oleates, etc.);

4. Organic matter containing aldehyde group (aldehyde, formic acid, formate, a certain ester of formate, etc.);

5. Petroleum products (pyrolysis gas, pyrolysis gas, pyrolysis gasoline, etc.);

6. Coal products (coal tar);

7. Natural rubber (polyisoprene).

2. It can make the acidic potassium permanganate solution fade inorganic substances

1. Compounds of 2-valent sulfur (H2S, hydrosulfuric acid, sulfides);

2. 4-valent sulfur compounds (SO2, H2SO3 and sulfites);

3. Hydrogen peroxide (H2O2, where oxygen is 1 valence).

1. React with unsaturated hydrocarbons such as olefins, alkynes, and diolefins to fade the potassium permanganate solution; It reacts with benzene congeners (toluene, ethylbenzene, xylene, etc.) to discolor the acidic potassium permanganate solution.

2. Redox reaction with phenol to discolor potassium permanganate solution.

3. Redox reaction occurs with aldehydes and other aldehyde organic matter, so that the potassium permanganate solution fades.

4. React with the inorganic reducing agent with reducing properties to fade the potassium permanganate solution.

Potassium permanganate Chemical Properties:Potassium permanganate has strong oxidizing properties and is commonly used as an oxidant in laboratories and industries, and decomposes in case of ethanol. It slowly decomposes into manganese dioxide, potassium salts and oxygen in acidic media.

Light has a catalytic effect on this decomposition, so it is often stored in brown bottles in the laboratory.

As can be seen from the elemental potential diagram and the oxidation state diagram of the free energy, it is extremely oxidizing. In alkaline solutions, its oxidation is not as strong as in acidic solutions. When used as an oxidant, its reduction products vary depending on the acidity and alkalinity of the medium.

The ones that can fade the acidic potassium permanganate are:

1. Carbon-carbon double bond: Carbon-carbon double bond refers to the hybridization of one 2S sublayer and two 2P sublayers of carbon into three sp2 hybrid orbitals. These three sp2 hybrid orbitals are distributed in the same plane. The bond energy is greater than that of a single bond.

2. Carbon-carbon triple bond: Triple bond is a heavy bond (covalent bond) composed of three pairs of shared electrons between two atoms in a compound molecule, called a triple bond.

3. Hydroxyl group: The hydroxyl group has a chemical formula of -OH, which is a common polar group. Hydroxyl groups are mainly divided into alcohol hydroxyl groups, phenolic hydroxyl groups, etc.

4. Aldehyde group: a covalent bond in the carbonyl group is connected to the hydrogen atom and forms a monovalent atomic group, which is called an aldehyde group, the structure of the aldehyde group is -cho, and the aldehyde group is a hydrophilic group, so the organic matter with the aldehyde group (such as acetaldehyde, etc.) has a certain water solubility.

5. Amino group: Amino group is the basic base in organic chemistry, and all organic matter containing amino group has certain alkaline characteristics, which is composed of one nitrogen atom and two hydrogen atoms.

Potassium permanganate is used as a preservative, disinfectant, deodorant and antidote in medicine; In water purification and wastewater treatment, it is used as a water treatment agent to oxidize hydrogen sulfide, phenol, iron, manganese and organic, inorganic and other pollutants to control odor and decolorization; In gas purification, trace amounts of sulfur, arsenic, phosphorus, silane, borane and sulfide can be removed.

In mining metallurgy, oxidants for the separation of molybdenum from copper, the removal of impurities from zinc and cadmium, and the flotation of compounds; It is also used as a bleaching agent for special fabrics, waxes, greases and resins, an adsorbent for gas masks, and a colorant for wood and copper.

Common reducing agents are acceptable.

In organic matter, when the molecule contains structure.

Unsaturated bonds between carbon atoms (except benzene rings).

Primary alcohols (e.g., ethanol).

Aldehyde group (formaldehyde.

acetaldehyde, formalic acid), reducing aromatic compounds (phenol.

aniline), other benzene congeners and derivatives (e.g., toluene.

xylene, salicylic acid) and so on.

can fade acidic potassium permanganate.

There are also many inorganic substances.

Many common reducing substances.

For example, hydrogen sulfide.

Sulfur dioxide. Alkali metals +3 cr

iodine ions, etc. Among the common reducing agents, there are relatively stable reducing agents such as hydrogen and carbon monoxide that cannot fade the acidic potassium permanganate.

By the way.

If the acidic potassium permanganate solution is relatively concentrated.

It will also fade gradually during placement.

Water is oxidized as a reducing agent by the acidic potassium permanganate.

Many substances can be oxidized by the acidic potassium permanganate, which reduces potassium permanganate to low-cost manganese ions, which can fade.

The reason why any substance can exhibit its properties is determined by the structure of the substance. When the structure is changed, so is the nature. It's as if the tires turn because they are round.

If it becomes square, it can't be turned. The same goes for color. The reason why potassium permanganate is purple is because of the specific configuration.

If this configuration is destroyed, the color changes.

Reducing substances, which can reduce potassium permanganate to other substances, then the material basis of this realistic purple no longer exists, and from the surface of it, it is manifested as fading.

The substances that discolor potassium permanganate include unsaturated hydrocarbons, benzene homologues, phenols, aldehyde organic compounds, and inorganic reducing agents with reducing properties, as follows

1. Unsaturated hydrocarbons.

Unsaturated hydrocarbons are hydrocarbon compounds that contain carbon-carbon double or triple bonds in their molecules. Unsaturated hydrocarbons with double bonds are called alkenes because of the scarcity of hydrogen atoms, and alkynes with triple bonds mean that hydrogen atoms are lacking.

2. Homologues of benzene;

Homologues of benzene are the product of the substitution of hydrogen atoms on the benzene ring by alkyl groups. Its molecular formula is CNH2N-6 (N 6, N N), its molecule contains only one benzene ring, the side chain of the benzene ring is alkyl (—CNH2N+1), benzene ring and side chain interact with each other.

3. Phenol. Phenol is an organic compound with the chemical formula C6H5OH, which is a colorless needle-like crystal with a special odor, which is toxic and is an important raw material for the production of certain resins, fungicides, preservatives, and drugs such as aspirin. It can also be used for disinfection of surgical instruments and excrement treatment, **sterilization, anti-itching and otitis media.

Melting point 43, slightly soluble in water at room temperature, soluble in organic solvents.

4. Organic matter with aldehyde group.

A covalent bond in the carbonyl group is connected to the hydrogen atom and forms a monovalent atomic group, which is called an aldehyde group, the simple formula of the aldehyde group structure is -cho, and the aldehyde group is a hydrophilic group, so the organic matter with the aldehyde group (such as acetaldehyde, etc.) has a certain water solubility.

5. Inorganic reducing agent.

A reducing agent is a substance that loses electrons in a redox reaction. In general, reactants that contain a substance with an elevated valency are reducing agents. The reducing agent itself is reducible and oxidized, and its products are called oxidation products.

The reduction and oxidation reactions are carried out at the same time, that is, the reducing agent is oxidized itself while carrying out the redox reaction with the reduced substance, and becomes an oxidation product.

The substances that discolor potassium permanganate are as follows:Organic matter: reacts with unsaturated hydrocarbons such as olefins, alkynes, and diolefins to fade the potassium permanganate solution.

It reacts with benzene congeners (toluene, ethylbenzene, xylene, etc.) to discolor the acidic potassium permanganate solution.

A redox reaction occurs with phenol to discolor the potassium permanganate solution.

It undergoes redox reaction with aldehydes, glucose and other organic substances with aldehyde groups to fade the potassium permanganate solution.

Inorganic: React with reducing inorganic reducing agents (such as H2S, SO2, FeSO4, Ki, etc.) to fade the potassium permanganate solution.