Class 11th

Introduction and Vital Force Theory * Carbon exhibits tetravalency. * Carbon has the ability to successively bond to other carbon atoms to form long chain. This property of carbon is called as catenation. *Carbon also forms covalent bonds with hydrogen, oxygen, nitrogen, sulphur and halogens. These complex carbon compounds are known as organic compounds. * ... Read more

Group 13: General trends and Properties * Group 13 through 18 of the periodic table are called the p-block because the outermost electrons occupy p-orbitals. * Non-metals and metalloids are located in the p-block, as well as some metals. * The elements in period 3 and below can have expanded octets by involving d-orbitals in ... Read more

Alkali Metals: General Characteristics and Properties * The group1 metals are called the alkali metals. They are the most reactive metals. * They all have 1valence electron and all form +1 cations. * The alkali metals are good conductors, and they have a shiny, silvery appearance. * In flame tests, lithium forms a candy-apple red ... Read more

Dihydrogen: Preparation * Hydrogen is the most abundant element in the universe. * It has three isotopes – protium, deuterium and tritium. * In spite of its resemblance to both alkali metals and halogens, it occupies a separate place in the periodic table due to its unique behavior. * Its unique behavior also makes it ... Read more

Classical Concept * In a redox reaction oxidation and reduction occurs simultaneously. * Oxidation reactions are those reactions which include addition of oxygen or an electronegative element to a substance or removal of hydrogen or an electropositive element from a substance. * Reduction reactions are those reactions which include removal of oxygen or an electronegative ... Read more

Physical processes: Equilibrium * Equilibrium is a condition in which two opposing tendencies balance one another. * The opposing tendencies of a reversible change continue to take place with equal rates simultaneously at the equilibrium stage also. Hence, the equilibrium is called dynamic equilibrium. * Equilibrium can be established for physical as well as chemical ... Read more

Basic Terms and Concept – I * The branch of science that deals with the study of different forms of energy and the quantitative relationship between them is known as thermodynamics. * A system in thermodynamics refers to that part of the universe in which observations are made. * The part of the universe that ... Read more

Intermolecular Forces * Intermolecular forces are attractive and repulsive forces between the interacting atoms and molecules. * The force of attraction between the two temporary dipoles is known as dispersion force or London force. * Dipole –Dipole forces are attractive forces that act between the polar molecules with permanent dipole. * The Dipole –Dipole forces ... Read more