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In the transition element series startin...

In the transition element series starting from lanthanun `(""_(57)La)`, the next element hafnium `(""_(72)2Hf)` has an atom number, 72. Why do we observe this jump in atom number?

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This is because after `La(Z=57)` filling of 4f-orbital starts which is complete at atomic number 71. These 14 elements, therefore,belong to f-block and placed separately at the bottom of the periodic table.
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CENGAGE CHEMISTRY ENGLISH-APPENDIX INORGANIC VOLUME 2-Short Answer Type
  1. What happens when chromates are kept in acidic solution and dichromate...

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  2. Which is the most common oxidation state of lanthanoids?

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  3. In the transition element series starting from lanthanun (""(57)La), t...

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  4. Why does vanadium pentoxide acts as a catalyst?

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  5. The size of the trivalent cations in the lanthanoid series decreases s...

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  6. Give the general electronic configuration of actinoids

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  7. Write any two uses of pyrophoric alloys.

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  8. What is the maximum oxidation state in actinoids?

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  9. Name one ore each of manganese and chromium.

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  10. In the transition series, with an increase in atomic number, the atomi...

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  11. What is the effect of increasing pH on K2Cr2O7 solution?

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  12. What is the basic difference between the electronic configurations of ...

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  13. Why do transition elements show similarities along the horizontal peri...

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  14. Out of Al, Zn, Mg and Fe which is the densest element?

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  15. Write the electronic configuration of the element with atomic number 1...

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  16. Explain why transition elements have many irregularities in their elec...

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  17. Explain the following : The paramagnetic character in 3d-transition ...

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  18. Scandium forms no coloured ions, yet it is regarded as a transition el...

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  19. Assertion : Hydrochloric acid is not used to acidify a KMnO(4) solutio...

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  20. Why Sm^(2+) , Eu^(2+) and Yb^(2+) ions are good reducing agents , but ...

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