Give reasons for the following : (i) Nitric oxide becomes brown when released in air. (ii) Solid phosphorus pentachloride exhibits some ionic character. Or PCI_(5) is ionic in nature in the solid state. (iii ) Ammonia is a good complexing agent. Or Ammonia acts as a ligand

Give reasons for the following : (i) Nitric oxide becomes brown when

1.	Give reasons for the following : (i) Nitric oxide becomes brown when released in air. (ii) Solid phosphorus pentachloride exhibits some ionic character. Or PCI_(5) is ionic in nature in the solid state. (iii ) Ammonia is a good complexing agent. Or Ammonia acts as a ligand
Answer» Solution :(i) Nitric oxide readily combines with `O_(2)` of the air to form nitrogen dioxide `(NO_(2))` which has BROWN colour. `underset("(Colourless)")(2NO+O_(2))rarr underset("(Brown)")(2NO_(2))` (ii) `PCl_(5)` is ionic in the SOLID state because it exists as `[PCl_(4)]^(+)[PCl_(6)]^(-)` in which the cation is terahedral and the anion in octahedral. (iii) Due to presence of a lone pair of ELECTRON on `N, NH_(3)` acts as a complexing agent (ligand). As a RESULT, it combines with transition metal cations to form complexes. For example : `underset("Silver chloride Diamminesilver (I) chloride")(AgCl+2NH_(3)rarr[Ag(NH_(3))_(2)]Cl)` `underset("Copper sulphate Teraamminecopper (T) sulphate")(CuSO_(4)+4NH_(3)rarr[Cu(NH_(3))_(4)]SO_(4))` `CrCl_(3)+6NH_(3)rarrunderset("chloride")underset("Hexaamminechromium (III)")([Cr(NH_(3))_(6)]Cl_(3))`