During the period 1811-1886, the halogens were discovered. They are non-metallic elements such as: Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I) and astatine (At) which are the members of the halogen family. This family constitutes the group 17 of the periodic table. The word halogens have been derived from the Greek word “Halo” that … Read more
Group 15 of the modified long form periodic table consists of five elements: Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb) and Bismuth (Bi). These elements are collectively called the elements of nitrogen family. Nitrogen and Phosphorus are non-metals, arsenic and antimony are semi-metals or metalloids: bismuth is metallic although not so strong. Some important … Read more
Metal ions can complex with a variety of molecular species to form coordination compounds/ complex ions. These coordination compounds/complex ions differ appreciably from each other and also from their constituent species. These aspects of coordination compounds/complex ions have been exploited in many ways. Some of the major applications of the coordination compounds are described below. … Read more
Many applications are based on the phenomenon of adsorption. Some important applications of adsorption are as follows: A) Applications of the Adsorption of Gases on Solids i) For creating partial vacuum The phenomenon of adsorption of gases on solids has been used for creating partial vacuum particularly at low temperature. The vessel that has to … Read more
There are a number of steps involved in extraction of metals from its ores and is itself a science also. The science of extracting metals from their ores and utilizing them for various useful purposes is called metallurgy. The nature and properties of metals make its extraction difficult by using single method. Thus, it is … Read more
Group 13 of the long form of the periodic table consists of five elements: Boron (B), Aluminium (Al), Gallium (Ga), Indium (In) and Thallium (Tl). All these elements collectively are named as boron group elements, because Boron (B) is the first element of this group. These elements form the first group of the p-block elements. … Read more
The reaction rates vary with the concentration of the reactants. The experimental results show that the reaction rates do not always show similar concentration-dependences. In many cases, the rates are found to be proportional to the first power of concentration. There are many reactions in which the rates varied to the second or even third … Read more
A galvanic cell consists of two half-cells. In other words, a galvanic cell consists of two electrodes dipping into the same or two different electrolytes. There are several types of electrodes. Some commonly used electrodes are: a) Metal-Metal ion electrode A metal-metal ion electrode consists of a metal rod or plate dipping into a solution … Read more
The process of mixing of the atomic orbitals is called hybridization. There are different types of hybridization like sp2, sp3, sp, sp3d, sp3d2, sp3d, dsp2,d2sp3. The atoms of third period elements have vacant d orbitals. Since, the energy of 3d orbitals is comparable to the energy of the occupied 3s and 3p orbitals (the energy … Read more
There are some common methods used from preventing the rusting of iron which are described here below: i) By surface coating Rusting of iron can be prevented by coating the iron surface with oil, grease, paint and varnish, etc. Image source: Tampasteel ii) By electroplating iron with corrosion-resistant metals Certain metals like nickel, chromium do … Read more