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
The Rate of a Chemical Reaction The rate of a chemical reaction can be defined as the amount of the reaction which occurs in unit time. The rate of a reaction is measured by choosing certain properties of the reaction which will indicate how far the reaction has gone, and whose magnitude can be observed … Read more
Slow reactions Chemical reactions that occur very slowly and can take a long time for completion are called slow reactions. Usually covalent compounds are involved in slow reactions. Some reactions can take days, weeks and months to complete; they are called very slow reactions. For example, Milk may take several hours or a day to convert to curd, while … 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
Laboratory method of preparation acetic acid Ethanoic Acid (Acetic acid – CH COOH) Ethanoic acid is the second member of the homologous series of carboxylic acids. In other words, vinegar contains about 5 to 8% acetic acid. We will now describe two methods for the manufacture of ethanoic acid. In the first method, ethanoic acid … Read more
Preparation of Oxygen Oxygen is prepared in lab generally in two ways either by the application of heat or no application of heat. Using heat: Oxygen in lab is prepared by heating the mixture of powdered potassium chlorate and manganese dioxide in the ratio 4:1 in a hard glass test tube. The oxygen gas is … Read more
Preparation of nitrogen Nitrogen is found in both free and combined states. It occupies 78.07% by volume. Nitrogen can be prepared: By heating copper in air: Firstly, air is passed through lime water and then concentrated sulphuric acid to make the air free from carbon dioxide and moistures respectively. The air contains only nitrogen … Read more
The Rate of a Chemical Reaction The rate of a chemical reaction can be defined as the amount of the reaction which occurs in unit time. The rate of a reaction is measured by choosing certain properties of the reaction which will indicate how far the reaction has gone, and whose magnitude can be observed … Read more
Metallurgy of Copper Copper Mining: The commonest ore used in the extraction of copper is Chalcopyrite (CuFeS2) also known as Copper Pyrites and other such sulfides. The percentage of copper in the actual ore is too low for direct extraction of copper to be viable. The concentration of ore is required and it is done by the Froth … 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