Can unsaturated organics fade potassium permanganate?

In general, the strong oxidizing properties of potassium permanganate will open the double and triple bonds.

bonds, to form carboxylic acids or ketones or carbon dioxide, depending on the substance.

Judgment. But there are special cases, some aromatic substances do not fade, like benzene, because there are large bonds, the stability is very high, to open these.

Organics require a stronger oxidizing agent.

Chemistry is not mathematics.

Matter has particularities.

Generally, double and triple bonds are OK.

Not necessarily. Good luck!

Make an acidic potassium permanganate solution.

Fading organic matter:

1. Unsaturated hydrocarbons (olefins, alkynes, diolefins, styrene.

etc.); The double bond in the unsaturated hydrocarbon is called "alkene", which means that the hydrogen atom is "rare"; The one with three bonds is "alkyne", which means that the hydrogen atom is "lacking". In addition to this, there are aromatic hydrocarbons.

For example, "benzene". The double and triple bonds of unsaturated hydrocarbons are not very strong and are easy to break, and are prone to electrophilic substitution reactions and electrophilic addition reactions.

2. Homologues of benzene; The molecule contains a benzene ring, which means that the hydrogen on the benzene is replaced by a hydrocarbon group, and the composition conforms to CNH2N-6, which means that the composition is different by one or several CH2 atomic clusters, and only a series of hydrocarbons that meet these two points are benzene homologs.

3. Derivatives of unsaturated hydrocarbons (enols, enal, oleic acids, halogenated hydrocarbons, oleic acid, oleates, oleates, etc.); A series of compounds formed by the substitution of hydrogen atoms in hydrocarbon molecules by other atoms or clusters of atoms are called derivatives of hydrocarbons, in which other atoms or clusters of atoms that substitute hydrogen atoms make the derivatives of hydrocarbons have special properties different from those of the corresponding hydrocarbons.

4. Organic matter containing aldehyde group (aldehyde, formic acid, formate, a certain ester of formate, etc.); The system names the ester group more than the aldehyde group, and it is named according to the ester group, which belongs to the ester. But there is an aldehyde group, which has the properties of aldehydes.

5. Petroleum products (pyrolysis gas, pyrolysis gas, pyrolysis gasoline, etc.); The resulting pyrolysis gas is a complex gas mixture, which mainly contains ethylene, propylene, and butadiene.

In addition to unsaturated hydrocarbons, it also contains methane.

Ethane, hydrogen, hydrogen sulfide.

etc.); The olefin content in the pyrolysis gas is relatively high.

6. Coal products (coal tar.

Coal tar is mainly used for fractionating various phenols, aromatic hydrocarbons, alkanes, etc.

Potassium permanganate (KMno4) is a commonly used oxidizing agent that appears purple in solution. Some substances will react with KMno4 to cause the potassium permanganate solution to fade, mainly in the following cases:

Reducing agent: A strong reducing agent can reduce potassium permanganate to manganese ions (Mn2+), resulting in a loss of purple color. Common reducing agents include ferrous sulfate, hydroxide, sulfide, sulfite, ammonium hydroxide, etc.

Organics: Organics containing multiple bonds and reactive hydrogen can react with potassium permanganate, causing it to fade. Such as sugars, phenols, hydroxy acids, etc.

Acids: Concentrated sulfuric acid and concentrated hydrochloric acid can break down potassium permanganate and produce oxygen and manganese dioxide (Mno2), causing the purple color to disappear.

It should be noted that when judging the cause of discoloration, different factors should be considered comprehensively to avoid missed diagnosis.

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 Siqin and forms a monovalent atomic group, which is called aldehyde group, the structure of aldehyde group is -cho, and the aldehyde group is a hydrophilic group, so the organic matter with 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.

If you're a high school student, I suggest you keep in mind the common organics that can discolor acidic potassium permanganate.

Because acidic potassium permanganate is highly oxidizing, it reacts with reducing organic matter, and then acidic potassium permanganate fades. And the reductive organic matter means that it easily gets electrons, which also means that it contains empty orbitals.

It can be seen that CC double bonds, CO double bonds, hydroxyl groups, amino groups, etc. may contain reducing substances.

So that we can understand.

The ones that will make the acidic potassium permanganate fade are:

1.Olefins, alkynes, diolefins and other organic compounds containing CC double or triple bonds, and of course aromatic olefins containing benzene rings are also listed.

2.Alcohols and phenols and other organic substances containing hydroxyl groups, of which alcohol is directly oxidized to carboxylic acids, while phenols do not need to be mastered (I guess they are oxidized to p-quinones like oxygen).

3.For organic matter containing aldehyde groups, note that the aldehyde group is not the carbonyl group, because ketones cannot fade the acidic potassium permanganate.

4.Amine-containing organic matter, amide-containing organic matter.

5.Aromatic hydrocarbons with aliphatic chains, such as toluene, ethylbenzene, styrene, ......

6.esters, which are first acidically hydrolyzed into alcohols and carboxylic acids, and then oxidized by the acidic potassium permanganate.

Knowing which ones can fade so that the ones that don't fade are also easy to get.

saturated aliphatic hydrocarbons (alkanes); Ether; Ketones; benzene, naphthalene, anthracene; carboxylic acids and their derivatives (except amides), such as carboxylic acids, acyl halides, anhydrides, etc.; Aliphatic hydrocarbons containing only nitro, sulfonic acid, halogens and other substituents without empty orbitals or benzene, naphthalene, anthracene, such as nitrobenzene, benzenesulfonic acid, chloroform, bromobenzene, etc.

By the way, not being able to fade does not mean that it cannot react, nitro, sulfonic acid, and halogen will react with the acid in acidic potassium permanganate, and the same is true for anhydride and acyl halide, but it will not fade because it does not react with potassium permanganate.

It seems complicated, but in fact, you remember that the 1st, 2nd, 3rd, and 5th are already enough to spend in high school, and I hope it will help you.

The organic matter that fades the acidic potassium permanganate solution is:

1) unsaturated hydrocarbons; For example, hydrocarbons that contain carbon-carbon double bonds or carbon-carbon triple bonds.

2. Homologues of benzene; Toluene, xylene, ethylbenzene, etc.

3) derivatives of unsaturated hydrocarbons; Some halogenated hydrocarbons containing carbon-carbon double bonds or carbon-carbon triple bonds. For example, ethyl bromide.

4) some alcoholic organic compounds; For example, propylene alcohol.

5) Organic matter containing aldehyde groups: aldehyde, formic acid, formate, formate;

6) Petroleum products (pyrolysis gas, cracked gas, cracked oil);

7) Natural rubber.

Hello! The substances that can fade "acidic potassium permanganate" have reducing substances, which in organic chemistry are mainly unsaturated bonds, phenol, toluene and substances containing these functional groups.

It can make acidic potassium permanganate fade organic matter: unsaturated organic matter (containing -c c- or -c=c-).

Homologues of benzene (must contain hydrogen): toluene, ethylbenzene, etc.

Substances containing aldehyde groups. Because they have reductive functional groups.

It can fade the acidic potassium permanganate inorganic: most of the elements in the intermediate valence state can be oxidized by it.

Because potassium permanganate is very oxidizing.

For example, H2SSO2

h2o2cl2

HCLO etc.

Just memorize these in high school, too many will not pass the test!

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.

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

It reacts with inorganic reducing agents with reducing properties (such as H2S, SO2, FeSO4, Ki, HCl, etc.) to fade the potassium permanganate solution.

Containing double bonds (including special bonds of benzene) and highly reducing ones, which can discolor the highly oxidizing potassium permanganate.

Substance. Cause.

SO2SO2 is reducible and reacts with potassium permanganate to fade it.

ch2=ch2

In the category of organic matter, unsaturated carbon-carbon bonds (including triple bonds) are oxidized, causing them to fade.

Homologues of benzene.

For example, toluene) potassium permanganate oxidizes the methyl group on the sympathetic chain to a carboxyl group, thus forming benzene.

acid, thus fading the acidic potassium permanganate.

Aldehyde. The aldehyde group is highly reducible, so a redox reaction can occur, causing it to fade.