What is the smallest particle that makes up a substance?

A molecule is the smallest unit in which a substance can exist independently and keep all the chemical properties of the substance unchanged. It is formed by the combination of atoms of one or several elements (the general term for atoms with the same atomic nuclear charge number), in a certain number and manner. An elemental molecule, which is made up of one type of atom, such as hydrogen molecule H2, oxygen molecule O2, ozone molecule O3, etc.

Compound molecules, which are made up of several atoms, such as the water molecule H2O, the ammonia molecule NH3 (N is the nitrogen atom), etc. In the molecule, different combinations of atoms can form different substances, such as ch3ch2oh and ch3och3 (c is a carbon atom), although the number of atoms of the same kind is the same, but the former is an alcohol molecule, while the latter is an ether molecule, and the properties are completely different. Small molecules, with only a few atoms; Large molecules (called polymers) can contain thousands of atoms.

So the scales of different molecules can vary greatly.

An atom is the smallest unit that makes up elemental and compound molecules. It is a particle that can no longer be divided in a chemical reaction. It is the smallest unit of matter of an element.

More than 100 elements have been discovered, but each element has its own isotope (the same number of protons in the nucleus, but the number of neutrons is different), and new isotopes are being created all the time. So the number of atoms is much greater than the number of elements. For example, there are three isotopes of hydrogen, which are called hydrogen (H), deuterium (D), and tritium (T), and the latter two atoms play the same role as hydrogen atoms in chemical reactions, but there are more neutrons in the nucleus, so the mass is different, and it is also called hydrogen, heavy hydrogen, and super heavy hydrogen.

Together with oxygen atoms, they can form water (H2O), heavy water (D2O), and superheavy water (T2O), respectively. For complex atoms, there are more electrons outside the nucleus, and their operation is more complex, so I will not repeat it here.

The nucleus is the centrosome of an atom. It is composed of protons and neutrons. The nucleus is positively charged, and the number of charges is equal to the number of protons it contains.

Its mass, which is almost equal to the total mass of the atom, has a radius of about several 10-13 centimeters (depending on the number of nucleons contained). The structure of the nucleus is being studied, and the rough view is that it is spherical and deformable, both rotating and vibrating, much like the case of molecules.

The nucleon (a collective term for protons and neutrons) is the basic unit that makes up the nucleus of an atom. Each nucleon is made up of 3 quarks. Currently, Quark is still imprisoned in a nucleus, and there is no way to escape.

Quarks are the basic units that make up strongly interacting particles (hadrons, such as nucleons). There are 6 categories called 6 "tastes" of quarks. There are 18 flavors for each flavor, including 3 colors of red, blue, and green.

"Taste" and "color" here are just categorical terms, and they have no literal meaning. As we will see later, in the world of particles, each particle has its antiparticle (the antiparticle has the opposite charge to the particle, or the spin j is the opposite). So, the total number of quarks is not 18, but 36.

The above shows that although everything in the universe is very different and has different forms, it can eventually be decomposed into several particles.

A molecule is a tiny unit of matter, and it is the smallest particle that can exist independently and maintain all the original chemical properties of a substance.

So far, there is no conclusive conclusion, and it is currently believed to be quarks and gluons.

The atom is subdivided into neutrons, protons, electrons, and quarks.

What is the smallest unit of matter that is composed? Not an atom or a proton neutron, but it.

No, because matter seems to be infinitely divisible, and the smallest particles found now will no longer be smallest in a few years.

If there is anything that is the smallest particle that maintains the chemical properties of a substance, it is a molecule, so to speak.

Chemical properties are the properties of substances that exhibit in chemical changes. In a chemical reaction, the molecule will change, and if the molecule does not change, it means that no chemical reaction has occurred; Whereas, atoms do not change in chemical reactions. Therefore, molecules are the smallest particles that maintain the chemical properties of matter, not atoms.

The answers are not accurate, you can go and see the new textbook. A substance made up of molecules, the chemical properties of which are maintained by molecules, and a substance that is directly constituted by atoms, whose chemical properties are maintained by atoms. Ionic compounds will not be used for investigation.

Don't worry about it, just ask you questions during the exam. This proposition is inherently unscientific, for example, ionic compounds have no molecules at all, only ions.

Broadly speaking, elemental matter made up of atoms is also called a molecule.

It is true that the atom is the smallest unit in chemistry, but it is not possible to maintain the chemical properties of matter. Atoms have definite chemical properties, and if atoms are the smallest particles that maintain the chemical properties of matter, then different substances have the same chemical properties.

Just like substances made up of molecules (O2 and O3), their chemical properties are different. This class is held by molecules.

Like you said, some substances (such as metals) are made up of atoms, but they don't have molecules at all, so the smallest particles of this kind of matter are atoms.

A molecule is the smallest particle that maintains the chemical properties of a substance. That's right.

Atoms are smaller than molecules, but they do not maintain the chemical properties of the substance.

Just remember it.

When you answer the test , you will generally not be wrong . Because in a certain sense, the primitives can be said to be a single primitive, and this argument does not help the students to understand it in the first place, and all the answers are solved. There will be no such questions after that.

Considering that the atomic level is the transfer of electrons, it is more like the physical aspect.

According to modern scientific research, it has been determined that quarks are the smallest units of constituent matter found today.

A quark is an elementary particle that participates in strong interactions and is also the basic unit that makes up matter. Quarks combine with each other to form a composite particle called hadrons. The most stable of hadrons are protons and neutrons, which are the units that make up the nucleus of an atom.

Due to a phenomenon called "quark confinement", quarks cannot be directly observed or separated, but can only be found in hadrons. For this reason, much of what we know about quarks comes indirectly from the observation of hadrons.

Quarks have a variety of intrinsic properties, including electric charge, color charge, spin, and mass. In the Standard Model of particle physics, quarks are the only elementary particles that can withstand all four fundamental interactions (electromagnetic, gravitational, strong, and weak).

In addition, quarks are the only known particles with a non-integer elementary charge. Each flavor of a quark has a corresponding antiparticle called an antiquark, which is different from a quark only in that some of its characteristics are the same size as the quark but the symbol is different.

Learn the physical sense

The microscopic structure of matter is revealed, the world is made up of matter, and our world is the world of matter; Matter is made up of molecules; Molecules, in turn, are made up of atoms; Atoms are formed by the collision of nuclei and electrons; The nucleus is made up of protons and neutrons; Protons and neutrons are made up of smaller quarks, and so on.

molecules and their sizes.

1) After the 17th century, scientists put forward the concept of molecules on the basis of the research of their predecessors, especially in the study of the chemical properties of matter.

2) The smallest particles that make up a substance and can still maintain their chemical properties are called molecules. Note three meanings: a molecule is a particle that makes up a substance (not the smallest particle that makes up a substance); Molecules maintain the chemical properties of the substance; Molecules are the smallest particles that maintain the chemical properties of a substance.

If the molecules continue to be separated, the resulting smaller particles will not be able to maintain the chemical properties of the substance.

3) Molecules have a single original molecule, such as the copper molecule, which is made up of a copper atom; The molecule is a multi-atomic molecule, such as a water molecule, which is made up of two hydrogen atoms and one oxygen atom.

4) The molecule is very small, its diameter is only a few tens of nanometers (nm).At a standard atmospheric pressure, there is about one molecule in 1 cm3 of air and about one water molecule in 1 cm3 of water.

What are the particles that make up matter are as follows:

1.Molecules are the particles that make up matter, and different molecules must make up different substances.

2.A molecule is a type of particle that maintains the chemical properties of a substance.

When a substance composed of molecules undergoes a physical change, the molecules that make up the substance themselves do not change and still maintain the chemical properties of the substance;

When a chemical change occurs, the molecules that make up the substance are changed and become molecules of other substances, and they no longer maintain the chemical properties of the original substance.

Use a molecular point of view to distinguish mixtures from pure positive substances, physical and chemical changes.

1.The difference between mixtures and purities is analyzed and understood from two different perspectives: macro and micro.

The essential difference between a pure substance and a mixture is understood in a macroscopic way, in which only one substance is contained in a pure substance, while a mixture contains two or more substances, and its components are simply mixed, and the various substances still retain their original properties.

Microcosm (molecular point of view) understands that a substance made up of the same molecule is a pure substance, a substance composed of multiple molecules is a mixture, and the molecules of various substances do not react chemically with each other.

Since the components in the mixture are uncertain, they do not maintain certain properties, and there is only one molecule in the pure substance, so the pure substance has a fixed property.

2.Understand physical and chemical changes from both macro and micro perspectives.

In the macroscopic aspect, no new matter is formed in the physical change, whereas in the chemical change, new matter is formed.

There is no new molecule formation in the microscopic physical change, whereas there is new molecule formation in the chemical change in the foci.

The basic particles that make up substances include molecules, atoms and ions, and molecules, atoms, and ions can directly constitute substances, usually metals and solid non-metal elements are composed of atoms, and salts and alkalis are composed of ions.

The molecule is a whole that is bound together by the atoms in accordance with the bonding order and spatial arrangement of the atoms, and the bonding order and spatial arrangement relationship is called the molecular structure, due to the interaction between the atoms in the molecule, the physical and chemical properties of the molecule not only depend on the type and number of constituent atoms, but also depend on the structure of the molecule.