8.21 Explain giving reasons:

(i) Transition metals and many of their compounds show paramagnetic behaviour.

(ii) The enthalpies of atomisation of the transition metals are high.

(iii) The transition metals generally form coloured compounds.

(iv) Transition metals and their many compounds act as good catalyst. 

8.21 (i) Transition metals and many of their compounds show paramagnetic behavior- Paramagnetic behaviour is shown by transition metals as paramagnetism is due to the presence of unpaired electrons which have a magnetic moment associated with its spin and angular momentum, as the orbital angular momentum is satisfied in the first transition series. So the paramagnetic is only due to the unpaired electrons.

(ii) The enthalpies of atomisation of the transition metals are high- Enthalpies of atomization is the enthalpy change when 1 mol of gaseous atoms is formed from its element in its defined physical state under standard cond

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8.21 (i) Transition metals and many of their compounds show paramagnetic behavior- Paramagnetic behaviour is shown by transition metals as paramagnetism is due to the presence of unpaired electrons which have a magnetic moment associated with its spin and angular momentum, as the orbital angular momentum is satisfied in the first transition series. So the paramagnetic is only due to the unpaired electrons.

(ii) The enthalpies of atomisation of the transition metals are high- Enthalpies of atomization is the enthalpy change when 1 mol of gaseous atoms is formed from its element in its defined physical state under standard conditions (298.15K, 1 atm). In case of the transition metals enthalpies are high due to high effective nuclear charge and a large number of valence electrons which also leads to strong metallic bonding.

Eg: 515 KJ/mol for Vanadium,473 KJ/mol for Titanium

(iii) The transition metals generally form coloured compounds- Transition metals are generally coloured because of absorption of radiations which fall in the visible region as on obtaining energy electrons jump from one d-orbital to another.

(iv) Transition metals and their many compounds act as good catalyst- Transition metals and their compounds act as good catalysts due to its ability to show variable oxidation state and form complexes, another reason is that they provide a suitable surface for reaction to take place.

Eg: Vanadium Oxide in contact process, Finely divided iron in Haber's Process.

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<p><strong>8.21 (i) Transition metals and many of their compounds show paramagnetic behavior-&nbsp;</strong>Paramagnetic behaviour is shown by transition metals as paramagnetism is due to the presence of unpaired electrons which have a magnetic moment associated with its spin and angular momentum, as the orbital angular momentum is satisfied in the first transition series. So the paramagnetic is only due to the unpaired electrons.</p><p><strong> (ii) The enthalpies of atomisation of the transition metals are high-&nbsp;</strong>Enthalpies of atomization is the enthalpy change when 1 mol of gaseous atoms is formed from its element in its defined physical state under standard conditions (298.15K, 1 atm). In case of the transition metals enthalpies are high due to high effective nuclear charge and a large number of valence electrons which also leads to strong metallic bonding.</p><p>Eg: 515 KJ/mol for Vanadium,473 KJ/mol for Titanium</p><p><strong> (iii) The transition metals generally form coloured compounds-&nbsp;</strong>Transition metals are generally coloured because of absorption of radiations which fall in the visible region as on obtaining energy electrons jump from one d-orbital to another.</p><div><div><picture><source srcset="https://images.shiksha.com/mediadata/images/articles/1687154146phpiY1gOj_480x360.jpeg" media=" (max-width: 500px)"><img src="https://images.shiksha.com/mediadata/images/articles/1687154146phpiY1gOj.jpeg" alt="" width="288" height="162"></picture></div></div><p><strong> (iv) Transition metals and their many compounds act as good catalyst-&nbsp;</strong>Transition metals and their compounds act as good catalysts due to its ability to show variable oxidation state and form complexes, another reason is that they provide a suitable surface for reaction to take place.</p><p>Eg: Vanadium Oxide in contact process, Finely divided iron in Haber's Process.</p>

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