Why are molecules the smallest particles that make up matter?

molecules and their sizes.

1) After the 17th century, scientists put forward the concept of molecules on the basis of previous research, especially in the process of studying 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 separate, 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, it is only a few tens of nanometers (nm) in diameter. 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.

False proposition, proven.

Counterexamples, metals, etc.

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

Scientific research has found that any substance is composed of extremely small particles, and we call the smallest particles in it that maintain the chemical properties of a substance a molecule. Molecules are made up of atoms. Atoms refer to the basic particles of chemical reactions, and atoms are inseparable in chemical reactions.

With the development of science, atoms are considered to be composed of electrons, protons, neutrons, and they are collectively known as subatomic particles.

Molecules are made up of atoms, but ions are not, and ions are formed by the loss or gain of electrons from one atom. Matter is made up of particles, and particles here do not refer specifically to atoms. It's just a tiny particle.

Not all matter is made up of molecules, atoms, and some are made up of ions. Matter is made up of extremely tiny, invisible particles, common particles that make up matter are molecules, atoms, ions, etc., they are all microscopic particles.

Objects are made up of matter, which is made up of smaller particles – molecules, atoms or ions – which are so small in size that they are usually measured in units of 10 m=.

Not the parsing:

The theory of molecular motion holds that all matter is composed of molecules (atoms), molecules are always moving irregularly, and there is gravitational and repulsive force for interaction between molecules.

When people understand the concept of "field" and discover special substances that are not composed of molecules (atoms), such as electric fields, magnetic fields, electromagnetic waves, especially people's understanding of the wave-particle duality of light (which is essentially electromagnetic waves), people understand this kind of "special" matter - substances that have energy but are not composed of the smallest particles

Classical physics holds that all matter is made up of tiny particles such as molecules, atoms, etc.

But modern physics has gained a better understanding of the material world.

Through the in-depth study of electric fields, magnetic fields, and electromagnetic fields, these fields are actually a kind of matter.

Although they are not made up of tiny particles such as molecular atoms, they have some properties of matter, such as they have momentum, have energy, and many more.

Yes. Matter is made up of molecules or atoms, which in turn are made up of atoms, which in turn can be divided into nuclei and electrons. The nucleus of an atom can be divided into protons and neutrons.

Yes, molecules, atoms are not the smallest particles, atoms are made up of nuclei and extranuclear electrons, and the nucleus is made up of neutrons and protons.

All matter on Earth is made up of atoms or molecules.

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.

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) respectivelyFor 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 quarksThere 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 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.

I think: First of all, "some comrades say that molecules in a broad sense include molecules, atoms, and ions", which is reasonable and accepted by everyone in scientific practice. In other words, there are broad and narrow definitions of molecules.

Secondly, "molecule is the smallest particle that retains the chemical properties of a substance" can be understood as for a specific substance (separately), which can be completely understood as: a molecule is the "smallest unit" of "a certain substance" to maintain "its unique" chemical properties, that is, taking iron as an example, the iron element is continuously divided, and the scale is getting smaller and smaller, and at a certain size level, iron happens to still retain all the chemical characteristics of its macroscopic scale, then this scale is the molecular scale of iron. The smallest unit of iron that can still retain the chemical properties of the macroscopic is the "iron molecule", and other substances are analogous; Or understand it on a broad basis. (Note that the molecule is a concept that was introduced by considering the separability of matter, as if you were a member of the family.)

I should have a correct understanding of the above statement, and read the original sentence several times.

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 change and become molecules of other substances, which no longer retain the chemical properties of the original substance.

Use a molecular point of view to distinguish between mixtures and purities, 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 physical change in the microscopic aspect, whereas there is new molecule formation in the chemical change.

Definitely not, it can only be said that atoms are the smallest particles in a chemical reaction.

Atoms also include the nucleus and extranuclear electrons, and the nucleus also has protons and neutrons, so the atom is certainly not the smallest particle that makes up matter.

No, atoms are the smallest particles in a chemical reaction. Atoms are divided into nuclei and extranuclear electrons, and nuclei are divided into protons, neutrons, etc.

a. The basic particles that make up matter are molecules, atoms and ions, such as water is composed of water molecules, so the statement is wrong B. The atom is the smallest particle in chemical change, so the statement is wrong C. The atom can no longer be divided into chemical changes, but it can also be divided into the nucleus and the extranuclear electron in the structure, so the statement is wrong D. The mass of the atom is mainly concentrated in the nucleus, and the mass of the electron is relatively small with the proton and neutron, which is often ignored Therefore, the mass of the atom is about equal to the sum of the mass of the proton and the neutron The statement is correct Therefore, D is selected

An atom contains a nucleus and an electron, and the nucleus contains protons and neutrons, which in turn are made up of quarks.

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