Chemistry What does the section on the amount of a substance mean?

The quantity of matter: is a fundamental physical quantity, which represents a collection containing a certain number of particles, with the symbol n. The unit is mole, referred to as mole, and the symbol is that the number of particles contained in the particle collective is the same as the number of carbon atoms contained in it, which is about.

1. Avogadro's constant: It is a physical quantity that can be defined as the number of particles contained in a substance per unit of matter. The symbol is na, and the unit is mol 1, which can be expressed as na= mol 1.

It is the ratio coefficient between the molar mass of the particle (i.e., the mass at one mole) and its mass.

2. Molar mass: The mass possessed by a substance as a unit of substance is called molar mass. The symbol is m, and the commonly used unit is g mol.

When the molar mass is measured in g·mol 1, it is numerically equal to the relative molecular mass or relative atomic mass of the substance. For a pure substance, its molar mass is fixed and constant, whereas the mass of a substance varies with the amount of matter of the substance.

3. Quantity and concentration of substance: The amount of solute B contained in the solution per unit volume represents the physical quantity of the solution and the concentration of the substance called solute B. The symbol is c (b), and the unit is mol l (or mol·l 1), etc.

The volume of the solution cannot be equated to the volume of the solvent, but should be the actual volume of the solute after it is dissolved in the solvent. Soluts can be substances or molecules or ions.

4. Gas molar volume: The volume occupied by the gas per unit of substance is called the gas molar volume, the symbol is vm, and the commonly used units are l mol or (l·mol 1) and m3 mol (or m3·mol 1). The molar volume of the gas varies at different temperatures and pressures.

In standard condition kpa), the molar volume of gas vm=.

5. Avogadro's law: At the same temperature and pressure, any gas of the same volume contains the same number of molecules. This law is called Avogadro's law.

Avogadro's law applies only to gases, not to solid and liquid substances. Only gases with the same temperature, pressure, and volume have the same number of molecules. VM is the embodiment of Avogadro's law.

The quantity of matter is one of the seven fundamental physical quantities in the International System of Units (the seven basic physical quantities are: length (unit: meter), mass (unit: ).

kilograms), time (unit: seconds), current intensity (unit: amps), luminous intensity (unit:

Candela), temperature (unit: Kelvin), quantity of matter (unit: moles), it is a physical quantity of the whole noun, like the concepts of "length", "mass", "time", etc.

Its symbol is n, and the unit is mole (mol), which is referred to as mole. The quantity of a substance is the ratio of the number of particles (n) (e.g., molecules, atoms, etc.) contained in a substance to Avogadro's constant (na), i.e., n=n na.

The value of Avogadro's constant is the number of carbon atoms contained in c, which is approx. It is a physical quantity that associates a certain number of particles with a measurable macroscopic substance. The quantity of matter is a physical quantity that represents a collective containing a certain number of particles, with the symbol n.

The unit of quantity of matter is mole, referred to as mole, and the symbol is mol. Internationally, it is stipulated that the number of particles contained in a 1mol particle collective is the same as the number of carbon atoms contained in carbon-12).

Quantity of substance (mol) = mass of substance (kg) Molar mass of substance (kg mol).

The amount of solute contained in a unit volume of solution is used to express the physical quantity of the solution, which is called the concentration of the solute.

International System of Units (derived units): mol m.

The number of particles of any substance contained in 1 mol is called Avogadro's constant, na=, which is an infinite non-cyclic decimal in 1 mol.

Note< The number of particles of any particle of 1>1mol is Avogadro's constant, which does not change due to changes in conditions such as temperature and pressure.

2. > application of Avogadro's law and theory (at the same temperature and pressure, the same volume of any gas contains the same number of molecules) should be satisfied: the substance is a gas at the given temperature and pressure.

I hope I can help you with your doubts.

The quantity of a substance is a unit of quantity, indicating the number of particles contained in the substance, containing - Avogadro's constant na - then the number of particles is 1mol, Avogadro's constant na is about a particle is 1mol particles, that is, molecules, atoms, protons, neutrons, electrons, chemical bonds, etc., such as na H2, the amount of hydrogen matter is 1mol 1molH2, containing na H2 molecules, containing 2 na H atoms.

It is a term that expresses the amount of matter.

For example, I usually know: 2 is called 1 pair (or 1 pair), 12 is called 1 dozen, and 500 pieces of paper are called 1 collar paper.

In the same way, the Avogadro constant particle (molecule, atom, ion) is called 1 mole of a molecule, atom, ion.

The amount of matter applies to microscopic particles, and microscopic particles include many, not just the ones you say!

The ratio of the amount of substances that produce hydrogen by reacting with sufficient amounts of hydrochloric acid with the same mass of sodium, magnesium, and aluminum respectively is (1 23 : 1 12 : 1 9).

What is the mass ratio of the amount of sodium, magnesium, and aluminum that react with sufficient hydrochloric acid to produce hydrochloric acid? ( 1:2:3 )

The amount of H2 material generated by 1g of Na = mol, the amount of H2 substance generated by 1g of Mg = 1 24, and the amount of H2 substance generated by 1g of Al =

Therefore, the ratio of the amount of substances that produce the hydrogen gas is 1 23 : 1 12 : 1 9

Let the amount of substances be 1mol, so the amount of H2 substance generated by 1mol Na = , the amount of H2 substance formed by 1mol mg = 1mol, and the amount of H2 substance generated by 1mol Al =

So the mass ratio of the hydrogen produced is 1:2:3

In fact, it is "counting".

To calculate the number of particles in a certain amount of matter, then count them one by one.

But there are so many particles that a particle is artificially grouped into a single unit, called "mole", called Avogadro's constant. Any number of particles is "1 mole".

1 mole of the mass of a substance is called the "molar mass" of the substance, which is numerically equal to the relative molecular mass of the substance.

The purpose of their invention of this unit of measurement is to more conveniently link the number of microscopic particles with the macroscopic mass of matter, and the purpose is to measure 1 unit of proton or neutron with a mass of 1 g

However, there is a deviation in this amount for different substances, so carbon 12 is used as the standard.

It's very simple, for example, in the original match, we said how many there were, but now there are not 50 in a box, we say how many boxes. The same is true of the amount of matter, which is 1 mol per example of Avogadro.

Carbon is element six, so the number of protons is 6, and carbon is in the fourth main group, and the outermost electron number is 460g, and carbon is 60 12=5mol

The outermost electron number of all carbon atoms is 4*5 = 20mol or 20 na, and na is the Avogaro number = 23 power.

The total number of protons is 30mol.

The number of electrons in the outermost shell is 60g, 12g, per mol*4*23 to the 25th power.

The number of protons is the number of outermost electrons divided by 4 times 6, equal to the 25th power.