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(1)Why Zn is not regarded as transition element ?

                    (2)Define enthalpy of atomisation.

                    (3)Why Hg exists in liquid state ?
                    (4)Why the highest oxidation state of metal exhibited in its

                         oxides or fluoride only ?
                    (5)Why Cu+ is not known in aqueous solution ?



                    (6)Why the transition elements act as catalysts? Give two
                         examples of the reactions catalysed by them?

                    (7)Giving reasons, indicate which one of the following would
                         be coloured  Cu ,V ,Sc ,Ni .
                                                   3
                                                       2
                                           
                                              3
                    (8)Co(ii) is stable in aqueous solution but in the presence of
                         strong ligands and air it can get oxidized to Co(iii).
                    (9)Fe or Cu has higher melting point and why?

                                  2
                    (10) Co 2 orNi  has lower magnetic moment.
                    (11)What is the magnetic character of KMnO 4 ?

                    (12)Why HCl is not used in permanganetometry titration ?
                    (13) Write chemical equations for conversion of Chromite ore

                    to sodium chromate.
                    (14)Define lanthanoid contraction.

                    (15)What is the cause of lanthanoid contration ?

                    (16)Write down the consequences of lanthanoid contraction.
                    (17)Actinoid contraction is greater from element to element

                    than lanthanoid contraction. Why ?


                    (18)Why compounds of Ln(III) and Lu(III) are colourless ?


                    (19) What is the most common oxidation state of lathanides?

                    (20)Why do Zr and Hf exhibit  similar properties?
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