BPSC Prelims and Mains Notes, BPSC Test Series
Corrosion is defined as an attack on a material as a result of chemical, frequently electrochemical reaction, with the surrounding medium. According to this definition, the term corrosion can be applied to all materials, including non-metals. But in practice, the word corrosion is mainly used in conjunction with metallic materials. Why do metals corrode? Apart … Read more
Acid An acid is a substance which forms H+ ions as the only positive ion in aqueous solution. Examples:- Hydrochloric acid dissolved in water forms H+ and Cl– ions HCl —> H+ + Cl– Sulphuric acid dissolved in water forms H+ and SO42- ions H2SO4 —>2H+ + SO42- Nitric acid forms H+ and NO3– ions when dissolved in water HNO3 —> … Read more
Metallurgy concentration, roasting, smelting Roasting It is a process wherein the ore is heated either alone or with some other material in excess of air below the fusion point of the ore. Usually, this method is used for sulphide ores. In roasting, definite chemical changes take place to form oxide or chloride of the metal. … Read more
Properties of polyvinyl chloride What is Polyvinyl Chloride (PVC), and What is it Used For? Polyvinyl Chloride (PVC) is one of the most commonly used thermoplastic polymers in the world (next to only a few more widely used plastics like PET and PP). It is a naturally white and very brittle (prior to the additions of plasticizers) plastic. PVC has been around longer … Read more
Properties of teflon Polytetrafluoroethylene or PTFE (more commonly known as Teflon) is a particularly versatile ivory-white and opaque plastic fluoropolymer; it is made by the free-radical polymerisation of many tetrafluoroethene molecules, and is suitable for a wide range of applications in industries as diverse as aerospace, the food and drink industry, pharmaceuticals and telecoms. Produced by … Read more
Endothermic Reactions Endothermic reactions are those chemical reactions where energy is absorbed by the system from the surroundings mostly in the form of heat. The concept is applied in the physical sciences like chemical reactions where hear is converted to chemical bond energy by way of experiments. Common examples of endothermic reactions are cooking an … Read more
Properties of polythene Polyethylene is a thermoplastic polymer with variable crystalline structure and an extremely large range of applications depending on the particular type. It is one of the most widely produced plastics in the world (tens of millions of tons are produced worldwide each year). The commercial process (the Ziegler-Natta catalysts) that made PE … Read more
Ore An ore is a special type of rock that contains a large enough amount of a particular mineral (usually a metal) to make it economically practical to extract that mineral from the surrounding rock. Not all minerals are found in a large enough amount in one location to make it worth it to remove the ore … Read more
Properties of soaps and detergents Soap – Characteristics And Uses Soaps are excellent cleansing agents and have good biodegradability. A serious drawback which reduces their general use, is the tendency for the carboxylate ion to react with Ca+ and Mg+ ions in hard water. The result is a water insoluble salt which can be deposited on … Read more
Laboratory method of preparing alcohol Hydrolysis of Alkyl Halides This is a nucleophilic substitution reaction. R-X + KOHaq → R-OH The method is not satisfactory as olefins are also formed as by-products. However better yields is obtained by using moist Ag2O or aqueous K2CO3. Tertiary butyl halides mainly gives alkene due to dehydrohalogenation. Hydration of Alkenes This … Read more