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In the series Sc (Z = 21) to Zn (Z = 30)...

In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomisation of zinc is the lowest, i.e., `126" kJ "mol^(–1)`. Why?

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Enthalpy of atomisation depends on number of unpaired electrons. In Zn there is no unpaire election. As a result, metallic bonding is weak so that enthalpy of atomisation is low
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AAKASH INSTITUTE ENGLISH- ALCOHOLS, PHENOLS AND ETHERS-Assignment Section -D (Assertion - reason type question)
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  2. Assertion : Boiling point of p-nitrophenol is greater than that of o-n...

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  3. A : When C(2) H(5) - O- CH(3) is reacted with one mole of Hl then C(2...

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  4. A : When 3,3-dimethyl butan - 2 - ol is heated in presence of concentr...

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  5. A : In esterification reaction , HCOOH is the most reactive acid among...

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  6. A : Ethers can't be distilled upto dryness due to fear of explosion . ...

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  7. Phenol is less acidic than........... .

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  8. A : CH(3) - underset(O)underset(||)(C)-COOH gives haloform reaction ...

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  9. A : Diphenyl ether is prepared by Williamson synthesis . R : This...

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  10. A : Grignard's reagent is prepared in the presence of ether . R :...

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  11. A : CH(3) - underset(CH(3))underset(|)overset(CH(3))overset(|)(C)-CH=...

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  12. A : Two moles of Grignard reagent is consumed in the formation of ter...

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  13. A : bond angle in ether is slightly greater than normal tetrahedral an...

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  14. A : CH(3)-underset(CH(3))underset(|)overset(CH(3))overset(|)(C)-O-CH...

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  15. A : Ortho - cresol is weaker acidic than meta-cresol . R : It is d...

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  16. A : Among all ortho halophenol , fluorophenol is least acidic . R ...

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  17. A : In esterification reaction alcohol act as nucleophile . R : ...

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  18. A : Phenol is manufactured by Dow 's pocess. R : It involves the ...

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  19. A : Primary alcohol is prepared by the reaction of primary amine with ...

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  20. A : The reactivity order of alcohols is 1^(@) gt 2^(@) gt 3^(@) for ...

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  21. A : The dehydration of ethyl alcohol in presence of Al(2)O(3) at 633 ...

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