1. Give three points of difference between lanthanoids and actino… - Vidyadip

Question

Give three points of difference between lanthanoids and actinoids.
Give reason and select one atom$/$ion which will exhibit asked property:

$Sc^{3+}$ or $Cr^{3+} ($Exhibit diamagnetic behaviour$).$
$Cr$ or $Cu ($High melting and boiling point$).$

✓

Answer

S. No.	Lanthanoids	Actinoids
$1.$	Most of them are not radioactive.	All are radioactive.
$2.$	Don’t show a wide range of oxidation state.	Show a wide range of oxidation states.
$3.$	Most of their ions are colourless.	Most of their ions are coloured.

$Sc^{+3},$ because of absence of unpaired electron.
$Cr,$ because of presence of strong intermetallic bonding than $Cu.$

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