How to distinguish physical properties, physical changes! Chemical properties, chemical changes!

The properties of an object refer to the properties and characteristics of the object itself, including chemical properties and physical properties, and microscopically the interaction and arrangement interval between molecules, the activity of molecules and their affinity for other objects. When the arrangement between molecules is changed, or when the inherent molecules combine with foreign molecules to form new molecular chains, the object changes, which can be physical or chemical.

Chemical changes are often accompanied by physical changes, and physical changes are not necessarily accompanied by chemical changes. Physical change refers to the change of the physical properties (existence form, appearance and shape) of an object, which does not generate new substance, but only changes the external form of the original substance, such as the evaporation of water (from liquid to gaseous) and the breaking of porcelain bowls (from the whole to crushing). A chemical change is a change in the intrinsic properties of an object, a recombination of the internal structure of a molecule, and the formation of a new substance.

Physical change Chemical change.

Literally, you can see that there are variations in these two.

For example, ice becomes water (physical change).

Water is electrolyzed into H2 and O2 (this is a chemical change) and properties are properties that the object itself has.

For example, water freezes at a standard pressure of 0 (physical properties) chemical properties: SO2 has bleaching properties, etc

If you don't know, you can ask.

Physical change means that the substance itself does not change, and the corresponding physical property refers to the property that the substance does not need to undergo chemical change, or the property that the substance exhibits without a chemical reaction is called the physical property.

Chemical change refers to the change that is produced by other substances during the experiment, which is called chemical change. The properties that the corresponding substances exhibit when they undergo a chemical change are called chemical properties.

Categories: Education, Science, >> Learning Aid.

Analysis: Physical Change: Macroscopic: No new matter produces auspiciousness. Microscopic: The molecule does not change (e.g., a wooden stick breaks).

Chemical Change: Macroscopic: New substances are produced. Microscopic: molecules break down and atoms recombine (e.g., carbon combustion to produce carbon dioxide).

Physical properties: The properties of an object that are not reflected by discursive changes, such as color, density, boiling point.

Chemical properties: properties reflected through chemical changes, such as flammability and oxidation of the branch.

In fact, it can be judged whether it is a physical or chemical property like this: for example, density, which can be calculated by mass and volume. The calculation does not produce new matter, so it is a physical property.

Another example is flammability. However, a new substance is chemically changed. So it's chemical. Complete.

Physical changes do not produce new substances.

Chemical changes produce new substances.

Physical properties do not need to be reflected in chemical changes, such as hardness, density, color and other chemical properties are manifested in chemical changes.

Property is an intrinsic property of a substance, and change is a change in a property of a substance.

Physical properties such as mass, density, volume, color, odor, texture, melting and boiling point, solubility, etc., are properties that can be observed without chemical reactions. Chemical properties refer to the ability of a substance to react with a substance.

A physical change is a change in the physical properties mentioned above, while the substance itself (chemical formula) does not change. A chemical change is a change in matter. The original substance ceases to exist after chemical change, and a new substance is generated.

If the composition of something changes after a change, it is a chemical change, for example, hydrogen is ignited in oxygen to form water, which is a chemical change; If there is no change in its composition, but only a change in size and shape, it is a physical change. The properties that are only manifested in chemical reactions are chemical properties, such as iron rust, properties that do not involve the chemical composition of the molecules of matter, such as the aggregation state of matter (gas-liquid solid) and its changing state are physical properties. Do you understand?

A change in the absence of new matter is called a physical change. For example, glass breaks, wet clothes are dried, and objects fall to the ground.

A change in the formation of a new substance is called a chemical change. For example, firewood burns, iron rusts, and food spoils.

The properties of a substance that manifest itself in a chemical change are called chemical properties. For example, magnesium is burned in the air to form magnesium oxide, and ammonium bicarbonate is heated to produce oxygen, water and carbon dioxide.

The properties that matter exhibit without chemical change are called physical properties. Such as: color, state, odor, melting point, boiling point, hardness, density, solubility.

The difference between a chemical change and a physical change is whether or not a new substance is formed.

Let's talk about chemical change first: this change is that a new substance is created later (that is, after changing this thing, it cannot become its original appearance).

Physical change: This change is that no new substance is created later (that is, the thing can still change into its original form after changing).

So, next: chemical properties are what are presented during the "chemical change" process (e.g. reducibility, oxidation, flammability, etc.).

Physical properties are things you can know without having to make a "chemical change" to it (e.g., color, state, smell).

Melting point boiling point. Hardness and density are physical properties, and they only need to be measured and observed to know the data, and it is still the same after you measure and observe) (Ah, it is worth mentioning that "easy (difficult) to dissolve in water is a physical property, because it can be separated after dissolving in water).

If you don't understand in the future, you can also ask me.

Give points to points!

A physical change is a change in which no new matter is generated;

A chemical change is a change in the formation of a new substance;

The connection between them is that chemical changes must be accompanied by physical changes;

Physical properties are properties that can be expressed by chemical changes that are not made by chemical change; Such as the color, state, odor, melting point, hardness of the substance, etc.;

Chemical properties are properties that manifest themselves when there is a chemical change; Such as flammability, etc., are commonly used"Yes""Easy"、"Yes"Denote.

A change that does not produce a new substance is called a physical change, and a change that produces a new substance is called a chemical change.

The properties that do not need to be manifested through chemical changes are called physical properties, and the properties that must be realized through chemical changes are called chemical properties.

For example, alcohol volatilization is a physical change (because it is still alcohol), and alcohol combustion is a chemical change (because it is not alcohol when burned); The corresponding volatile alcohol is a physical property, and the combustible alcohol is a chemical property.

Relationship: When a chemical change occurs, a physical change must occur, and a chemical change does not necessarily occur when a physical change occurs.

See if there is a new substance generated, there is a chemical change generated by a new substance, and there is no physical change if there is no new substance, such as the reaction of water and metal sodium to produce sodium hydroxide is a chemical change, and the evaporation of water into water vapor is a physical change.

A chemical change is a change in the formation of a new substance;

A physical change is a change in which no new matter is generated;

Chemical properties are the properties involved in chemical changes.

Such as toxicity and flammability.

Physical properties are properties that involve physical changes.

Such as color, state, density.

Physical properties are the properties of the object itself, such as mass, volume, color, smell, etc., and the chemical properties can be basically understood as the chemical reactions that can occur in the object. Physical change, such as the change of water from liquid to gaseous, is a physical change, and the nature of matter does not change. A chemical change is a change in the nature of a substance, from one substance to another, such as carbon burning in the air to carbon dioxide, the process is a chemical change.

A physical change is a change in the formation of other substances.

A chemical change is a change that gives rise to other substances.

Physical properties refer to the properties of substances that do not need to undergo chemical changes to manifest themselves, and refer to the properties of substances that exhibit without chemical reactions.

Chemical properties are properties that are exhibited only when a chemical change occurs in a substance, which is called chemical properties.