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In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?

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प्रश्न

In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?

लघु उत्तरीय
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उत्तर

The electrons of the 3d orbitals of zinc are not used in bonding, whereas the electrons of the d orbitals of all the remaining metals of the 3d series are used in forming bonds. Hence the value of the atomization enthalpy of zinc is the lowest in the series.

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अध्याय 4: The d-block and f-block Elements - Intext Question [पृष्ठ ९५]

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एनसीईआरटी Chemistry Part 1 and 2 [English] Class 12
अध्याय 4 The d-block and f-block Elements
Intext Question | Q 4.2 | पृष्ठ ९५

संबंधित प्रश्न

Account for the following:

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Why do the transition elements have higher enthalpies of atomisation?


In 3d series (Sc to Zn), which element has the lowest enthalpy of atomisation and why?


How would you account for the following: Transition metals form complex compounds.


How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements?


Calculate the ‘spin only’ magnetic moment of \[\ce{M^{2+}_{( aq)}}\] ion (Z = 27).


For M2+/M and M3+/M2+ systems, the E° values for some metals are as follows:

Cr2+/Cr −0.9 V
Mn2+/Mn −1.2 V
Fe2+/Fe −0.4 V
Cr3/Cr2+ −0.4 V
Mn3+/Mn2+ +1.5 V
Fe3+/Fe2+ +0.8 V

Use this data to comment upon:

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How would you account for the following:

Of the d4 species, Cr2+ is strongly reducing while manganese (III) is strongly oxidising.


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 in basic medium.


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Assertion: Separation of \[\ce{Zr}\] and \[\ce{Hf}\] is difficult.

Reason: Because \[\ce{Zr}\] and \[\ce{Hf}\] lie in the same group of the periodic table.


Assertion: The highest oxidation state of osmium is +8.

Reason: Osmium is a 5d-block element.


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\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]


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The compounds of \[\ce{Ti^4+}\] ions are colourless due to ______.


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