In 1919 sommerfeld presented a modified and elaborated version of Bohr’s atomic model. The fine structure of the hydrogen emission lines of the structure is of fine structure.
To explain this, Sommerfeld suggested that it is not necessary that all the electrons of the same orbit have the same energy, the energies of some electrons of the same orbit may be different from the energies of the other electrons.
In other words, the main energy levels are divided into sub-energy levels. It is not necessary that all the electrons of the same orbit rotate on…
In other words, atoms whose atomic numbers are the same but different mass numbers are called isotopes of each other.
Since the mass of an atom and its atomic weight are approximately equal. Therefore, the above definition of isotopes can also be written as this — atoms whose atomic numbers are the same but different atomic mass are called isotopes of each other.
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Three isotopes of the hydrogen element are known. Their atomic number is 1 and their mass numbers are 1, 2 and 3 respectively. …
According to the law of mass action, the quantitative effects of temperature, pressure, concentration, volume and other factors on the equilibrium of a chemical reaction can be studied. For the qualitative study of these factors on equilibrium, franchise science le chatelier introduced a generalized rule in 1884 called le chatelier’s Principle.
French chemist Henry Louis Le Chatelier,
According to this rule –
If a system in equilibrium is subjected to a charge of concentration, pressure, temperature, volume etc., the equilibrium shifts in the direction that tends to undo the effect of the change.
Formaldehyde gives all the normal tests of the aldehyde group. It gives pink color with schiff reagent, silver mirror with tollan reagent and red precipitate with fehling solution.
Specific testing of formaldehyde is as follows.
A drop of 0.5% aqueous resorcinol solution is found in 1 ml of dilute aqueous solution of formaldehyde. This mixture is slowly found in the surface of 5 ml of concentrated H2SO4. Carefully stir the test tube in such a way that both the surfaces are not lost. A ring of red violet is formed at the meeting of both surfaces.
Add 1 ml of…
When the -CHO group is attached to a hydrogen or carbon atom, it is called an aldehyde group. And the related compound is called aldehyde.
Example: -CHO group in HCHO is associated with H, so it contains aldehyde group and it is an aldehyde. In CH3CHO, -CHO is associated with group C, so it also has an aldehyde group and is also an aldehyde. -CHO group is present in HCOOH but it is associated with O, so aldehyde group is not present in this compound.
Toluene: benzaldehyde is obtained from oxidation of toluene by chromyl chloride CrO2Cl2. This reaction is called Etard’s Reaction.
C6H5CH3 + 2CrO2Cl2 → C6H5CH(OCrOHCl2)2 → C6H5CHO
Benzaldehyde is also obtained by oxidation of acidic solution of toluene’s manganese dioxide MnO₂. In the presence of vanadium pentoxide(V₂O₅) at 350°C, oxidation of toluene by air oxygen also yields benzaldehyde.
Benzenal chloride: benzenal chloride (C7H7Cl) gets benzaldehyde on heating with lead nitrate solution in the atmosphere of carbon dioxide gas.
2C6H5CH2Cl + Pb(NO3)2 → 2C6H5CHO + PbCl2 + 2HNO2
To make benzaldehyde in the laboratory, take 10 grams of benzene chloride, 8 gram lead…
Laboratory method: from tin and HCl reduction of nitrobenzene: in the laboratory, aniline is made by the reduction of nitrobenzene by tin and HCl.
Sn + 4HCl → SnCl4 + 4H
C6H5NO2 + 6H → C6H5NH2 + 2H2O
Industrial manufacturing: from ioran and HCl reduction of nitrobenzene: Anealin is made by reduction of nitrobenzene by moist iron shavings and HCl in commercial quantities.
Fe + 3HCl → FeCl3 + 3H
C6H5NO2 + 6H → C6H5NH2 + 2H2O
Chlorobenzene: Chlorobenzene gets aniline at high pressure with ammonia in the presence of Cu2O and when heated to about 250°C.
C6H5Cl + NH3…
Aniline: Benzenediazonium chloride is obtained by replicating aniline with a mixture of NaNO2 and HCl at 0–5°C. Chlorobenzene is obtained by heating benzenediazonium chloride in the presence of cupreous chloride and hydrochloric acid.
C6H5NH2 + NH2 + HCl → C6H5 — N = N — Cl + 2H2O
The first reaction is called diazotization reaction and the second reaction is called sandmeyer reaction.
C6H5 — N = N — Cl → C6H5Cl + N2
Chlorobenzene is obtained by mixing a mixture of benzene vapors, hydrogen chloride gas and oxygen (oxygen) at 250°C…
Benzene was first discovered by Michael Faraday in 1825. Faraday obtained benzene from a distillation of while fish oil. Hofmann obtained it in 1845 from the fractional distillation of bitumen. A few decades from now, bitumen(coil tar) was the major source of benzene. Now the major source of benzene is petroleum.
In the laboratory, benzene is made by distillation of sodium benzoate and soda lime.
C6H5COONa + NaOH → C6H6 + Na2CO3
Such compounds have been obtained from natural sources such as resins, balsam and bitter almond oil, which contain special type of smell.
These compounds are called aromatic compounds due to their special type of smell. The word aromatic originated from the Greek aroma meaning aroma.
The study of these compounds revealed that the percentage of carbon atoms in them is higher than corresponding aliphatic compounds. It has been found that the simplest of these compounds is the derivative of benzene and most other compounds benzene.
Therefore, initially benzene and its derivatives are called aromatic compounds…