Soul of Chemistry

 GE - I (Generic Elective) Chemistry Practical Experiments 1. Estimation of Oxalic Acid by titrating it against standard KMnO4 Solution (0.098 N). Principle: The reaction between oxalic acid and potassium permanganate is an example of redox (oxidation reduction) titration. KMnO4 acts as the oxidising agent and oxalic acid as the reducing agent. They react as per the following reaction: 2KMnO 4 + 3H 2 SO 4 -------> K 2 SO 4 + MnSO 4 + 5O H 2 C 2 O 4 .2H 2 O + O ---------> 2CO 2 + 3 H 2 O Thus the equivalent mass of oxalic acid is equal to half of its molecular mass, i.e., 126/2 = 63. The given oxalic acid solution is taken in 100 ml standard  measuring flask and made up to  the mark with water. It is then titrated against standard KMnO4 solution. From the volume  of KMnO4 solution and Oxalic acid solution  and the normality of KMnO4 solution the  normality of oxalic acid solution is determined from which the amount of oxalic acid in whole  of the supplied solution is calcu

 Organic Chemistry Question and Answer: Basic Concept: Organic Reaction Intermediates  Q. What are carbocations and what are their types? Ans: Organic cationic species having +ve charge on an sp2 hybridised carbon atom is called a carbocation. This positive charge on carbon may further be delocalised due to shifting of electrons by resonance involving an unshared pair of electrons or a double or triple bond at allylic position. These are called the classical carbocations .     Examples include:      CH 2  = CH – CH +           ,      PhCH 2 +            ,         R 2 CH +                These are formed by heterolytic cleavage of a C -X bond or by protonation of alcohols or by protonation of alkenes.     But in a nonclassical carbocation, the positive charge on carbon is delocalised by a  single bond  or sometimes by a  double or triple bond that is not present at the allylic position. Unlike classical carbocation the positively charged  carbon is not an sp2 hybridised carbon.