In this post, we shall learn about Avogadro’s Constant or the Formulation of Avogadro in Chemistry
. While understanding the basic concepts behind the development of Avogadro’s Constant
. Let’s see what we are cover today from Avogadro’s Constant (See the table of contents).
Dalton’s Atomic Theory
The key to scientist Dalton’s atomism is that every element is made up of a number of very small indivisible particles. The name of these smallest particles is atoms. Atoms of various basic substances in chemical reactions are formed in simple proportions of whole numbers to form compounds. Such as 1: 1, 1: 2, 1: 3 and so on. Dalton never imagined a molecule in his atom.
Concept of the Molecule
basic materials and composite materials, both as an atom was the smallest particle. As a result, many complications and problems arise. To solve this problem, Avogadro introduced the concept of molecules. According to him, a substance is made up of two smallest particles, namely [i]
atoms and [ii]
[i] Atom: – Atom is the smallest indivisible particle of a substance. Atoms may or may not exist independently, and atoms participate in chemical reactions.
[ii] Molecules: – The smallest particle of all elemental or compound substances is a molecule. Molecules can exist independently and all religions of matter are present in molecules.
Types of the molecule
Maintaining the imagination of scientists dalatanera Avogadro atom molecule introduced the imagination. According to him, atoms combine to form molecules. Atoms – (1) basic molecules and (2) compound molecules.
 Elementary Molecule: – A molecule formed by atoms of the same element is called a basic molecule.
- Atomicity: The number of an element, a molecule made up of atoms, the number of the elements that Atomicity.
The structure of basic molecules can be varied –
(A) One- atom molecules : eg Na, K, Ca, C etc.
(B) Bi-atomic molecules: eg H2, O2, N2 etc. Their atomicity = 2
(C) three- atom molecules : eg ozone (O3); . Its atomicity = 3
(D) Four atomic molecules: S4, P4 etc. Their atomicity = 4
(E) polyatomic molecules: eg S8;. Its atomicity = 8
(F) disabled molecules: such as He, Ne, A, etc. Their molecules and atoms are synonymous.
 Compound Molecule: – consists of multiple elements by atomic molecule to molecule compounds. Such as ammonia [NH3], water [H2O], nitric acid [HNO3] molecules etc.
Avogadro’s Law (Constant)
Avogadro published a source by revising Bergelias’ project (equal number of atoms in all gases at the same pressure and heat ). It is known as Avogadro’s formula. The formula is that all gases have the same number of molecules at equal pressure and heat.
- Explanation: – According to Avogadro’s formula, if there is an N- number of molecules in x cc oxygen [O2] at the same pressure and temperature, x cc will have the same n- number of molecules in carbon dioxide (CO2) or x cc ammonia [NH3].
Short Questions and Answers From The Formulation of Avogadro
Reconciliation of law Gaseous Volume and Dalton’s Atomic Theory by Avogadro’s law (Constant)
Experiments show that 2 volumes of hydrogen chloride gas are produced at the same pressure and temperature by chemical mixing of 1 volume hydrogen and 1 volume chlorine.
Suppose, at the same pressure and temperature during the experiment, 1 volume of hydrogen gas contains n- number of hydrogen atoms. According to sources at the same pressure and temperature, then 1 volume of chlorine avogadro’s in n sankhyaka chlorine molecules and the volume of hydrogen chloride in 2 2n sankhyaka be hydrogen chloride molecules. Therefore, by expressing the reaction with the number of molecules, it can be said,
- n -numerous hydrogen molecules + n -numeric chlorine molecules = 2n -numerous hydrogen chloride molecules
- Or 1 hydrogen molecule + 1 chlorine molecule = 2 hydrogen chloride molecules
- Or 1 molecule hydrogen + 1 molecule chlorine = 1 molecule hydrogen chloride.
- Since according to Avogadro’s formula 1 molecule is hydrogen = 2 atomic hydrogens and 1 molecule chlorine = 2 atom chlorine.
So it can be written:
1 atom hydrogen + 1 atom chlorine = 1 molecule hydrogen chloride ie 1 molecule hydrogen chloride is formed by the combination of 1 hydrogen atom and 1 chlorine atom. This is not against atomism, because atoms are inseparable but molecules are atoms. According to the Gauss-Lucas gas volume formula in this reaction (different gases at the same temperature and pressure are chemically combined in straight proportions to the full number of volumes), the ratio of the volume of the reactant and the reaction gases at the same heat and pressure is H2: Cl2: HCl = 1: 1: 2. Simple ratio to whole numbers.
Statement of Deduction From Avogadro’s Law
The following conclusions are obtained from Avogadro’s sources:
(1) Basic gases other than inert gases (eg hydrogen, oxygen, nitrogen, etc.) are two-atoms.
(2) The molecular mass of a gas [M] is twice the vapour density of a gas, that is, M = 2D.
(3) The proof of pressure and heat is the amount of one gram molecule of all gases (elemental or compound) volume is 22.4 litres. This volume does not depend on the nature of the substance of religion.
Avogadro’s Number: – basic or complex molecules in one gram of a substance is the same number of molecules. This number is called the Avogadro number. This number is expressed by N.
Scientist Millikan evaluates this number. Avogadro number N = 6.023 x 1023; It is a constant number – it does not depend on pressure and warmth.
Again, NTP contains one gram-molecule gaseous volume = 22.4 litres. Thus, the number of molecules in a gas of 22.4 litres in proof pressure and heat is called Avogadro’s number.
Again, a gram-atom quantity is the number of atoms in an element, also called the number Avogadro. In both cases N = 6.023 x 1023.
Unit of the number of substances: –At present, the use of ‘moles’ as a unit in chemical calculations has been very simple and reasonable. One mole molecule, one mole atom or one mole ion means Avogadro-number N; That is, 6.023 x 1023 refers to the total amount of molecules, atoms or ions, which, when expressed in the gram, the gram molecular mass in the molecule, the gram-atomic mass in the atom, or the gram ionic mass in the ion. In the context of the concept of ‘mole’, instead of the conventional ‘gram-molecule’, gram-atom ‘,’ gram-ion ‘, now’ mole-molecule ‘,’ mole-atom ‘,’ mole-ion ‘are used. For this reason, the use of ‘mole’ in chemistry is very widespread.
to SI system ‘mole’ s definition : 0,012 kg of carbon -12 (C12) in the number of carbon atoms are, no matter the extent that the number of molecules or atoms or ions present is filled with the same amount brake ‘ one mole-atom ‘; Called ‘ one mole atom ‘ or ‘ one mole ion ‘.
Avogadro project or Avogadro formula is reasonable to say: – Avogadroproject was not possible to prove the authenticity of the trial immediately. So, by definition, it should be called the Avogadro project. But every decision made from this project can be proved on the basis of the information available. Therefore, it is relevant to say that Avogadro’s ideas about molecules do not project.
A molecule of an element or compound is about twice as large as a 1/12 of the mass of a carbon-12 (C12) atom, that number is the molecular mass of that element or compound.
That is molecular mass = mass of 1 molecule of an element or compound / 1/12 of the mass of carbon-12 (C12) atoms.
That molecular mass is just a number, not a single one.
According to this calculation, the molecular mass of oxygen = 32 implies that the mass of 1 oxygen molecule is 32 times heavier than 1/12 of the mass of 1 carbon – 12 (C12) atoms.
One gram-atomic mass or one gram-atom
The mass of a basic substance’s atomic mass is expressed as gram, the mass expressed in the village is called the gram-atomic mass or one gram-atom of that element. For example, the atomic mass of oxygen is 16, hence 16 grams of oxygen is called one gram of atomic oxygen.
Gram-Molecular Mass or Gram-Molecule or Gram Mole
If you express the molecular mass of any element or compound in the village, then the mass expressed in the village is called gram-molecular mass or one gram-molecule or one gram-mole of that element. G-molake short Mole [Mole] says. For example, the molecular mass of oxygen = 32, therefore the gram-atomic mass of oxygen = 32 g. These 32 grams of oxygen are called one gram-molecule or one gram-mole of oxygen.
Vapour density or relative density
The mass of gas under the same pressure and heat is equal to the mass of hydrogen gas, which is called the vapour density or relative density of that gas.
That is, the vapour density of gas [D] = V mass of gas / V volume is the mass of hydrogen gas.
The amount of volume a gram-molecule of a basic or composite gas holds under certain pressure and heat is called the volume of gram-molecule or mole of that gas. The volume of moles depends only on pressure and warmth, not on the nature of the substance of the religion. The molar volume of any gas is 22.4 litres under proof pressure and heat. For example, the molar volume of one gram-molecule O2 or 32 g O2 in NTP = 22.4 litres. Thus, 2 g of molecules in NTP is any gas volume = 2 x 22.4 = 44.8 liters.