Chemistry

Ether is the anhydride of alcohol. R – O – R'

Alcohols are the organic compounds with -OH group as the functional group. They are monoalkyl derivatives of water.

Halo arenes are obtained by replacement of hydrogen atom of aromatic hydrocarbon by halogen.

Alkyl halides are esters of alcohols and hydracids. Based on the carbon to which halogen is attached, alkyl halides are classified into primary, secondary and tertiary halides.

Benzene is the parent member of Aromatic compounds. The compounds which resemble benzene in structure and properties are called aromatic compounds. Aroma means fragrant smell (pleasant smell).

Alkynes are commonly known as acetylenes. Acetylene is the simplest and important member of the alkyne series. Alkynes contain – C ≡ C –. General molecular formula of alkynes is C_nH_2n-2.

Alkenes are unsaturated hydrocarbons. These contain a C=C. They contain two hydrogens less than corresponding alkanes. Double bonded carbon undergoes hybridisation. These are otherwise known as Olefins.

General molecular formula of alkanes is C_nH_2n+2. These are saturated hydrocarbons.  They contain C-C and C-H bonds. They are commonly known as paraffins due to their less reactivity.

Organic compounds are carbon compounds and the study of chemistry of carbon compounds is called organic chemistry. Organic compounds contain Carbon, Hydrogen, essentially and Oxygen, Nitrogen, Sulphur, Phosphorus, Halogen frequently.

Environment constitutes air, water, soil, plants and atmosphere around us. The branch which deals with the relationship between living organisms and environment is called environmental chemistry.

The elements in which the differentiating electron enters the d-orbital of the penultimate shell are called d-block element. d-block elements are present in between electropositive s-block elements and electronegative p-block elements in the periodic table.

Helium, Neon, Argon, Krypton, Xenon and Radon are collectively known as noble gases or Aerogens or rare gases. They have completed s and p orbitals in the outer shell.

F, Cl, Br, I and At constitute the VII A group in periodic table. They are p - block elements and their outer shell configuration is ns²np⁵.

VI A group contains oxygen, sulphur, selenium, Tellurium and polonium belongs to p-block of periodic table. The first four elements are collectively called as chalcogens since many metals occur as oxides and sulphides.

VA group elements are Nitrogen (N) (7), Phosphorus (P) (15), Arsenic (As) (33), Antimony (Sb) (51), Bismuth (Bi) (83). These elements are called as pnicogens. Their compounds are called pnictides.

Almost all properties will show a normal trend from C to Si, But, beyond Si, the trend or change slows down due to ineffective screening caused by d and f electrons.

Boron, Aluminium, Gallium, Indium and belong to IIIA group of the Periodic table. The general outer electronic configuration of IIIA group elements is ns²np¹.

Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba) and Radium (Ra) are IIA elements. The oxides of these elements (CaO (Lime), SrO (strontia), BaO (Baryta)) are thermally very stable and basic in nature & hence, they are called alkaline earths.

Li, Na, K, Rb, Cs and Fr belongs to IA group. Oxides of Li, Na, K, Rb and Cs dissolve in water giving strong alkalies. So, these elements are known as alkali metals.

Hydrogen is the most abundant element in the universe. It is the 9th most abundant element in the earth's crust. It occurs only in the combined state except in volcanic gases where it occurs in free state.

Generally, metals occur as compounds in the earth crust. The compounds of metals which occur in earth crust, along with the earthy impurities associated with them, are called minerals.

Repetition of properties after intervals of atomic number values 2, 8, 18 and 32 is called periodicity. The properties are called periodic properties.

To simplify the study of chemistry of elements and their compounds, systematic classification is necessary. The first attempt was made by Dobereiner.

Adsorption: The phenomenon in which the molecules of a substance are attracted and adhered to the surface of a solid or liquid. Adsorption is a surface phenomenon. Adsorption is a exothermic reaction. Released heat is called Heat of adsorption.

The study of rates of chemical reactions mechanisms and factors affecting rates of reactions is called chemical kinetics.

Electrochemistry deals with chemical changes involving electricity. Some chemical reactions require electric current and some chemical reactions produce electric current.

Based on the direction of their occurrence, chemical reactions are two types.

A solution is a homogeneous mixture of two or more substances at molecular or ionic levels. Components of true solution can not be separated by filtration, settling, centrifugation.

The force of attraction between atoms or ions is called chemical bond. Formation of chemical bonds involved electrons and nuclei and mainly energy changes. Bond formation is exothermic and bond breaking is endothermic.

According to Dalton, atom is the smallest indivisible particle. But discharge tube experiments have proved that atom consists of some more smaller particles. Electrons, protons and neutrons are the fundamental particles of an atom.