Give reasons for the following:
(a) Red phosphorus is less reactive than white phosphorus.
(b) Electron gain enthalpies of halogens are largely negative.
(c) N₂O₅ is more acidic than N₂O₃ .

(a) Red phosphorus is more stable than white phosphorus. White phosphorus has angular strain in the P₄ molecule, which make it very unstable and highly reactive.
(b) The atoms have only one electron less than the noble gas configuration. Therefore, halogens have large Negative electron gain enthalpy.
(c) N₂O₅ is highly unstable because it is present in +5 oxidation state. This make N₂O₅ more acidic.