Why do objects turn to ash after fire burns

The origin of everything in the world is made of matter, for many plants and animals, they are composed of cells and trace elements, so in life we find that after the matter is burned, only a lump of ash remains. It is because these substances contain a large number of trace elements and minerals that can be burned and form gases will dissipate, and for those solids, they are not combustible, or the residues left by insufficient combustion. <>

Anyone who has burned firewood knows that when burning firewood, because the wood block and oxygen are fully finished, heat and light will be generated, so at this time, according to the conservation of energy, you will transform from solid to other forms of people, but after burning a large amount of wood, a mass of ash will be born, then this time is some of the carbon components and a lot of trace elements and minerals contained in it, because these substances can not be burned or are not fully burned and some remnants are left. And these substances are also difficult to easily get into the air, so they form the ash that we see. In fact, everything will leave a lump in the combustion process, but except for substances such as stones, their melting point is really high, and it is difficult to burn them all at ordinary temperaturesFor some substances that can be commonly found in charcoal and plastics, when burning, due to insufficient combustion or inability to burn, it leads to a cloud of ash left.

For many substances, their bodies are composed of trace elements and many minerals, so these substances can combine with oxygen to form some gases when burning, or it is burned out and converted into other forms of energy, and for those that remain, these are large particulate matter and residues that cannot be burned, or are not fully burned. <>

So these are the reasons why it leaves a cloud of ashes after you burn an object. These ashes are remnants that have not been fully combusted, or are not capable of combustion.

The question you are asking is itself wrong.

Some substances do not turn into ash after combustion, mainly depending on the chemical composition of the substance, which may be mixed with oxygen (hydrogen, carbon dioxide) during combustion.

and so on.

Finally, a new substance is generated, which may or may not be ash Of course, if it is burned at high temperatures for a long time, it will become ash by destroying its structure.

Because objects are made up of organic and inorganic matter, organic matter is combustible while inorganic matter is not. So when an object burns, there is something left, which is what you call ash (sometimes it can be the general shape of the object instead of ash, which is determined by the proportion of the object's organism and inorganism).

That is, it is because there is a non-combustible inorganic substance in the composition of the object.

That's a mineral that can't be burned.

1. The ash after the combustion of organic matter is an inorganic substance, which usually refers to a compound that does not contain carbon elements, but includes carbon-containing carbon oxides, carbonates, cyanide, carbides, carboanes, carbonyl**, alkane, and organic ligand complexes of metals, etc., referred to as inorganics.

2. Organic matter is organic compounds. In a narrow sense, organic compounds are mainly composed of carbon and hydrogen, and are compounds containing carbon, but do not include carbon oxides, sulfides, carbonic acid, carbonated socks high salt, cyanide, thiocyanide, cyanate, carbide, carboane, alkane, carbonyl, metal organic ligand complexes and other substances.

Objects are made up of organic matter and inorganic matter, organic matter can be burned to produce heat and light, inorganic matter can not be burned, most of it is composed of carbon, so it will be leftover.

Not all objects can turn to ash when burned, and some objects cannot burn themselves. Inorganic matter cannot be burned, and organic matter reacts chemically with oxygen and hydrogen in the air to form a new substance, which may turn into ash or other substances.

Because the object does not burn sufficiently, it leaves behind ash after combustion, which is the residue that has not been burned.

When an object is burned, all the organic matter is burned off, and the remaining combustion products are inorganic. This knowledge point is in the chemistry textbook of junior high school, and everyone who graduated from junior high school knows it.

Reusable elements: Elements that can participate in the mineral ion cycle. There are two main categories: one is the elements that are usually transported or utilized in the form of unstable compounds (such as nitrogen, phosphorus, magnesium, etc.); The other type is the element (such as potassium) that is always in an ionic state in the plant body

Reusable elements are preferentially distributed to areas with high metabolism. When plants are deficient in these elements, the deficiency first manifests itself in older tissues or organs.

Non-reusable elements: Usually elements that are not able to participate in the mineral ion cycle. Such as: calcium, iron, manganese, boron, etc. Among them, calcium is the most typical.

Non-reusable elements are fixed and rotten after they are assigned to the parts required by the implant. When plants are deficient in these elements, the deficiency first manifests itself in the younger tissues or organs.

Therefore, of the four options, only calcium is not available for utilization, and it cannot be transferred to new leaves when the leaves are senescent.

a. The wood has been completed, but the state of the wood has changed, and no new matter has been generated, which is a physical change, so A is wrong;

b. The fragrance of flowers is overflowing, which is the result of the movement of gas molecules, and there is no new substance generated, which is a physical change, so B is wrong;

c. The wax torch turns into ash, which is the combustion of the wax torch, which generates carbon dioxide and other remaining non-combustibles, and new substances are generated and chemical changes occur, so C is correct;

d. In the process of dripping water through stones, carbon dioxide participates in the reaction to generate new substances such as carbonic acid, which is a chemical change, so D is correct;

So choose CD

If you change the fire to high heat, it will not burn to ashes.

Hello! I'll explain it to you.

Combustibles such as plant carcasses, wood, paper, clothing, coal, etc., are mainly made of charcoal, wood, fiber (carbohydrates), calcium, iron, potassium, sodium, magnesium, etcand other minerals, when burning, the combustible part of the wood containing carbon produces a combustion oxidation reaction, generates carbon dioxide or other gases to diffuse into the air, and the remaining non-combustible and cannot be gasified becomes ash, which is the phenomenon of burning ash. Fuels such as alcohol, kerosene, and gasoline contain very few minerals, so they burn without ash.

If the fire is "replaced with high-temperature heating", in an environment with air, as long as the temperature reaches the ignition point of these combustibles, it will also burn to produce flames, and the result will still be "burned to ashes"; If the heating temperature does not reach the ignition point, it is roasted to dry residue. If the isolated air is "heated", there is no oxidation reaction, and only part of the substance vaporizes and runs away, and it will be burned into black charcoal. This is how charcoal is burned.

In terms of coal combustion, coal is composed of four parts: water volatiles, fixed carbon and ash. The water evaporates after being heated, and a part of the water and the hot carbon form water gas that continues to burn, which does not leave ashes. Volatiles are some complex organic compounds, the main components are hydrocarbons, followed by nitrogen and oxygen, which generally contain the ability to burn embers without leaving ashes.

The ash composition in coal is complex, most of them are not combustible, and some components have chemical changes at high temperatures, but they also leave solid ash. It is not possible to burn the fixed carbon completely, and the fixed carbon that is not completely burned remains in the ashes.

When solid plant fuel is burned, because the grass and trees contain some non-combustible inorganic substances, they leave ashes after combustion, which can be used as potash fertilizer.

The combustion of liquid fuel generally does not leave ashes, and in the case of insufficient oxygen**, a small amount of decomposed carbon may be left, such as the carbon deposits in the cylinder of a car.

Gas fuels rarely leave ashes when burning, and only when oxygen is insufficient, they can decompose carbon black, such as the yellow flame from a household gas stove can blacken the bottom of the pot. When producing "carbon black" from gaseous fuels, the combustion conditions are intentionally controlled to produce more "carbon black".

The ash after the combustion of organic matter is an inorganic substance, usually referring to a compound that does not contain carbon elements, but includes carbon-containing carbon-containing carbon-oxygen broad-qingide, carbonate, cyanide, carbide, carboane, carbonyl**, alkane**, organic ligand complexes of metals, etc., which are simply dry stoves called inorganic substances.

Organic matter is organic chemistry, and it is prudent to defeat the matter. In a narrow sense, organic compounds are mainly composed of carbon elements and hydrogen elements, and are compounds containing certain carbon, but do not include carbon oxides, sulfides, carbonic acid, carbonates, cyanides, thiocyanides, cyanates, carbides, carboanes, alkanes, carbonyls, metal organic ligand complexes and other substances.