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Showing posts from October, 2017

Elingham diagrame and its application ,isolation chapter

ELINGHAM     DIAGRAME    AND    ITS    APPLICATIONS;- Ellingham Diagram -Thermodynamics of Metallurgy 1 .Gibbs equation helps us to predict the spontaneity of a reaction on the basis of  enthalpy  and entropy values directly. 2. Ellingham proposed the Ellingham diagram to predict the spontaneity of reduction of various metal oxides. Ellingham diagram was basically a curve which related the Gibbs energy value with the temperature. Gibbs energy is given as:    ΔG = ΔH – TΔS Where ΔH is the change in enthalpy and ΔS is the change in entropy. With respect to a reaction, Gibbs energy can be related to the  equilibrium  constant as: ΔG o = – RTlnK Where K is the equilibrium constant. 3. when the reaction is exothermic, enthalpy of the system is negative, thus making Gibbs free energy negative. Hence, we can say that the re...

CBSE SAMPLE QUESTION PAPER 2018 CLASS XII CHEMISTRY(043)

                                     CBSE  SAMPLE QUESTION PAPER                                             CLASS XII CHEMISTRY(043)   Time: 3 hrs                                                                                                    MM: 70 GENERAL INSTRUCTIONS:            1. All the questions are compulsory.            2. Q. No. 1 to 5 are very short answer type, carrying 1mark each.           3. Q. No. 6 to 10 are short ans...

SOLUTION OF CBSE MODEL PAPER OF CHEMISTRY 2018

SOLUTION OF THE PAPER CBSE MODEL                                                                              (In brief) 111 Metal excess or anionic vacancies or F-centres 1 22 Catalysis by zeolites which depends on the shape and size of the reactants and the products as compared to those of the pores and cavitites of zeolites. 1 3 Neopentane or 2,2-Dimethylpropane 1 4 3-Chloropropanamine, CH 3 CH(Cl)CH 2 NH 2 ½, ½ 5 Three ions [Co(NH 3 ) 6 ] 2+ , 2Cl − ...