How to distinguish between chemical and physical properties?

We should pay attention to the difference between chemical change and chemical properties, such as candle burning is a chemical change; The phenomenon that a candle presents when it burns is its chemical properties. The chemical properties of a substance are determined by its structure, which in turn can be reflected by its chemical properties. The use of a substance is determined by its nature.

The chemical properties and chemical changes of a substance, when they change, other substances are formed, and this change is called chemical change, also known as chemical reaction.

Chemical properties are the properties of substances that exhibit in chemical changes. For example, the chemical properties of the substance category: acidic, alkaline, oxidizing, reducible, thermal stability and some other properties.

Chemical properties and chemical change are two different concepts, property is the property of matter, is the internal cause of change, and property determines change; The change is the specific manifestation of the property, and the chemical property can only be revealed in the chemical change. For example, alcohol is flammable, so when you ignite it, the chemical change of alcohol combustion can occur; Whereas the flammability (chemical properties) of alcohol is a conclusion drawn through the phenomenon of countless alcohol burns.

Chemical properties: The properties of a substance that can only be manifested in chemical changes are called chemical properties.

Chemical change: When a substance changes, a new substance is formed, and this change is called a chemical change, also known as a chemical reaction.

The properties that matter exhibit without going through chemical changes are called physical properties.

Some properties of substances, such as color, smell, taste, whether they are easy to sublimate and volatile, can be perceived by people's ears, nose, tongue, body and other senses, and some properties such as melting point, boiling point, hardness, electrical conductivity, thermal conductivity, ductility, etc., can be measured by instruments. There are also some properties that can be calculated through laboratory data, such as solubility, density, etc.

Neither the matter changed before or after the experiment. These properties are all physical.

It is advantageous to study the textbook carefully.

Chemical change is the creation of new substances, and physical changes are the creation of no new substances!

Chemical properties refer to the formation of new substances, and physical properties refer to the fact that the essence has not changed, and the properties have changed.

1. Physical properties.

Physical properties refer to properties that can be exhibited without chemical changes, such as color, state, odor, melting point, boiling point, hardness, density, etc. Nitrogen, for example, is a colorless, odorless gas with low melting and boiling points.

2. Chemical properties.

The properties of a substance that are exhibited in chemical changes are called chemical properties, such as flammability, stability, reduction, oxidation, etc., all belong to chemical properties.

Chemical properties need to undergo chemical changes to manifest, such as hydrogen is flammable, this property can only be manifested in the chemical reaction of hydrogen combustion, so it is a chemical property; Physical properties, on the other hand, are physical quantities that can be perceived and measured.

Judge the phenomenon of flammability, instability, acidity, alkaline, oxidation, flammability, reduction, complexation, toxicity, thermal stability, corrosiveness, metallicness, and non-metallic reaction with certain substances. The chemical properties of a substance can be known by the method of causing a chemical reaction of a substance.

For example, carbon is burned in the air to produce carbon dioxide; Hydrochloric acid reacts with sodium hydroxide to produce sodium chloride and water; Heating.

KCLO3 melts to rekindle the sparkled strips, indicating that KCLO3 can release O2 when heated to higher temperatures. Therefore, KCLO3 has the chemical property of thermal decomposition to produce O2.

Or, in layman's terms, the change in the formation of other substances during the experiment is called a chemical change.

Physical Properties: The properties of a substance that do not require a chemical change to manifest itself. As it is.

Chemical properties. Acidic liquids.

Color, state, odor, density, hardness, luster, solubility, volatility, electrical conductivity, ductility, etc., melting point, boiling point, thermal conductivity, etc.

Chemical properties: The properties of a substance that can only be manifested in a chemical change are called chemical properties. Such as: flammability, stability, acidity, alkaline, oxidation, reduction, etc., corrosiveness, etc.

Physical properties refer to external properties, such as color, state, etc., while chemical properties refer to properties that are exhibited through some reactions.

Whether the properties that are manifested in the chemical change are required.

What is needed is - chemical properties, what is not needed is - physical properties.

1. Chemical properties: flammable, flammable, oxidizing, reducing, corrosive, acidic, alkaline.

1. Flammability: the ability of materials or products to be burned with flames under the specified test conditions. For example, wood is flammable.

2. Combustibility: combustibles can be burned in a substance, which means that this substance has combustibility. For example, oxygen supports the combustion of combustibles.

3. Reducibility: Reducibility refers to the ability of atoms, molecules or ions to lose electrons in a chemical reaction. For example, hydrogen reacts with oxygen, and hydrogen is reducible.

2. Physical properties: solubility, melting point, boiling point, freezing point, volatility, color, electrical conductivity, thermal conductivity.

1. Melting point: the melting point of the substance, that is, the temperature when the solid and liquid states of the pure substance are in equilibrium under a certain pressure.

2. Boiling point: boiling is a violent vaporization phenomenon that occurs simultaneously inside and on the surface of the Qianqing liquid at a certain temperature.

3. Volatility: Volatility refers to the volatile nature or state, the nature and state of volatile, and volatility refers to the process of changing a compound from a solid or liquid to a gas or vapor.

Chemical properties are properties that are embodied by chemical reactions.

Physical properties are properties that are inherent and do not have to be embodied by chemical reactions.

For example, iron can react with dilute sulfuric acid, which is a chemical property of iron, which is reflected by the reaction with dilute sulfuric acid.

For example, iron can conduct electricity, and its conductivity is proved by experiments on electricity, and it does not become a chemical property if it does not involve a chemical reaction.

For example, iron is a silvery-white metal, and the silver-white color is directly visible to you, and it does not need to be expressed by chemical reactions, it is naturally a physical property.

A quick distinction can only be made by rote about common physical and chemical properties, physical properties: color, hardness, density, electrical conductivity, thermal conductivity, ductility, volatility, etc.

Chemical properties: toxic, oxidizing, reducing, acidic, alkaline, neutral, metal (non-metallic) activity, corrosive, etc.

When distinguishing between chemical properties and physical properties, it is mainly necessary to see whether there are new substances to be produced.

Chemical properties The properties that manifest themselves in chemical changes, chemical changes are usually used; Can, can, easy, will, make, come, etc. Such as: flammability, oxidation, reduction and stability.

Physical Properties: The properties of a substance that do not require a chemical change to manifest itself. Such as: color, taste, state, melting point, boiling point, hardness and density, electrical conductivity, thermal conductivity, rolling property, imitation slippery Yuxiang volatility and solubility.

Chemical changes lead to the creation of new substances. For example, the burning of magnesium belts produces a white powder.

Physical change is only a change in form, and there is no change in new matter. For example, three-state change, volatilization, fragmentation, dissolution, brine evaporation, diffusion.

1. The definitions are different

Physical properties: The properties of a substance that do not require chemical changes to manifest themselves, such as color, state, odor, melting point, boiling point, hardness, density, electrical conductivity, solubility, ductility, and so on.

Chemical properties: properties that are manifested by chemical changes, such as stability, flammability, oxidation, reduction, acidity and alkalinity, etc.

2. The characteristics are different

Physical properties: They belong to the category of statistical physics, that is, physical properties are properties exhibited by a large number of molecules, not by a single atom or molecule.

Chemical Properties: After the properties of the substance are measured, the original substance disappears. The oxidation, reduction, and universality of various substances exhibited by substances in chemical reactions are all chemical properties.

3. Common variations are different

Physical properties: Common physical changes include solid ice melted into water by heating, liquid water evaporated into water vapor, water vapor condensed into water, and gasoline volatilized.

Chemical properties: Common chemical changes include rusting of iron, fireworks at festivals, acid-base neutralization, etc.