How to distinguish physical properties from changes

Physical properties The properties of the object itself, the popular point is that it has been in life since birth, the nature determines the use, the use reflects the nature, and the physical change refers to the change in the form of the substance, such as the different pressure or temperature conditions, the form of the substance is different, and the physical change occurs, but the physical properties of the substance do not change, because the physical change does not produce new matter. For example, candle burning, the formation of wax oil, candle burning is a chemical change, the production of carbon dioxide and water, the chemical properties have changed, the formation of wax oil is a chemical reaction to produce heat energy, so that the candle melts, the physical properties change, and the candle from solid to liquid, is a physical change. Change is a process, while nature is inherent in the object itself, nature determines use, and use reflects nature.

That's how it's distinguished.

Physical properties include: color, state, odor, hardness, melting point, boiling point, density, solubility, volatility, electrical and thermal conductivity, adsorption, as long as the substance has these, it means that it is a physical property, chemical properties include: flammability, flammability, oxidation, reduction, acidity and alkalinity, stability and toxicity, as long as these are chemical properties.

What our teacher just talked about, now learn and sell, hehe.

Chemical change, where new substances appear from old substances, such as hydrogen and oxygen, to produce water, and this is the emergence of new substances, which is a chemical change.

Physical changes The substance has only undergone a change in state such as water freezing Ice or water It's just that the name changes due to the change of shape It's actually still water If you don't understand it, I'll go into more detail.

Physical properties refer to the properties of matter that do not change by itself.

A physical change is a change in the form of a substance.

I hope you are satisfied!!

Difference Between Physical Properties and Physical Changes:

1. The concept is different: physical change: the smallest particle that maintains the chemical properties of the substance itself remains unchanged, but the interval motion between the particles changes, and no new matter is generated.

Physical properties: The properties of substances that can be expressed without chemical changes, generally include: color, state, odor, hardness, magnetism, density, melting point, boiling point, solubility, freezing point, thermal conductivity, electrical conductivity, elongation, volatility, water absorption, etc.

2. Physical change is a process, and physical properties are a conclusion.

3. To describe physical properties, there are often words such as "easy", "can", "can", "will", "have" and so on.

For the study of chemistry, we must have a solid grasp of each knowledge point, and I have sorted out some knowledge points of physical properties and physical changes.

One refers to the properties of a substance that does not need to undergo chemical changes, and the other refers to the properties of a substance that exhibits a calculus without a chemical reaction, which is called physical properties.

Such as: color, odor, state, whether it is easy to melt, solidify, sublimation, volatile, 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.

There is no change in the formation of new substance. A physical change is simply a change in the shape and state of a substance, as opposed to a chemical change.

The basic three states of matter change, and no new matter is produced, so it belongs to physical change. Deliquescence of inorganic salts and alkalis such as NAOH, melting of ice, crushing of bile alum, etc.

The change that produces a new substance is a chemical change. Such as the rust of iron, the fireworks of festivals, the neutralization of acid and alkali, the burning of magnesium strips, and so on. On a macroscopic scale, it can be seen that various chemical changes produce new substances, which is characteristic of chemical changes.

The above is the knowledge points I have compiled about the physical properties and physical changes of the banquet source, I hope it can help you.

The main thing is that the characteristics are different. Physical properties: Physical properties 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.

Physical change (i.e., change in the state of matter): The process of physical change does not result in the formation of new matter. So that's the essential difference between the two.

Examples of common variations:Physical properties such as: color, odor, state, whether it is easy to melt, solidify, sublimation, volatile, and some properties such as melting point, boiling point, hardness, electrical conductivity, thermal conductivity, ductility, etc., can be measured by instruments.

The basic three-state change of matter, and no new substance is produced, so it belongs to physical change. Deliquescence of inorganic salts and alkalis such as NAOH, melting of ice, crushing of bile alum, etc. The distance between the atoms that make up the molecule does not change (the length of the chemical bond does not change), the shape and size of the substance changes, the molecule itself does not change, and the way the atoms are combined does not change.

The characteristics of the two are different: physical properties: physical properties 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; Physical change (i.e., change in the state of matter):

The process of physical change does not result in the formation of new matter.

Concept: There is no change in the generation of new matter. (Physical change is simply a change in the shape and state of the substance).

Substance: The smallest particle that maintains the chemical properties of the substance itself remains the same, except that the spaced motion between the particles changes, and no new matter is generated.

In fact, the fundamental difference between physical change and chemical change is that no new matter is formed during physical change, while chemical change (for example, the process of copper forming patina is chemical change).

Macro: No new matter is generated.

Microscopic: The distance between the atoms that make up the molecule does not change (the length of the chemical bond does not change), the shape and size of the substance changes, the molecule itself does not change, and the way the atoms bond remains unchanged.

The physical properties of substances such as color, odor, state, whether they are easy to melt, solidify, sublimate, volatile, 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 obtained and calculated through laboratory data, such as solubility, density, etc.

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

such as the evaporation of water; The candle is soft, not easily soluble in water, and the paraffin wax is generally white; paper shredding, etc. The properties that can be manifested without the change before chemical destruction are physical properties. The properties that are manifested by chemical changes are chemical properties.

Physical changes: three-state changes, dissolution, volatilization, sublimation, light and heat chemical changes: combustion, respiration, slow oxidation, redox reactions, food deteriorationPhysical properties:

Solubility, melting point, boiling point, freezing point, volatility, color, odor, state, electrical conductivity, thermal conductivity.

Chemical properties: flammability, combustibility, stability, oxidation, reduction, corrosiveness, acidity and alkalinity [or:

Chemical changes: Combustion of hydrogen, carbon monoxide, methane, magnesium bars burned in the air to form magnesium oxide, potassium chlorate decomposed by heat.

Physical Changes: Balloons**, Tire**, Water Freezes, Molten Iron Cast into Iron Pots, Water Vapor Condenses into Water Physical Properties: Color, Odor, State, Melting Point, Boiling Point, Hardness, Density, Solubility, Conductivity and Other Chemical Properties:

flammability, stability, oxidation, reduction, acidity and alkalinity].

A physical change is a change in the chemical properties of a substance before and after the change. The most talked about physical change in junior high school refers to the change of the three states of matter, that is, the change between the solid, liquid, and gaseous states.

The physical properties of a substance include solubility, melting point, boiling point, freezing point, hardness and softness, density, plasticity, elasticity, volatility, color, odor, state, electrical conductivity, thermal conductivity, magnetism, etc.

The chemical properties of substances have such aspects, such as oxidation, reduction, flammability, corrosiveness, flame retardancy, combustibility, acidity and alkalinity, etc.

For example, when water freezes, the chemical properties of H2O before and after the change are unchanged. Still the molecule is made up of one of two hydrogen atoms and one oxygen atom. In the acidity and alkalinity of the substance, the pH is equal to 7, which is neutral.

But the water freezes, and some physical changes occur, such as a change in temperature, a change in the state of matter, and a change in the distance between molecules. As a result, the lattice structure of the substance changes, and thus the properties of the substance also change, such as the hardness changes.

What is the difference between physical properties and physical changes.