In which of the following compounds there is a change in hybridisation of the underlined atom.

Step-by-step solution

In Al H ₃ , the central Al atom has 3 bond pairs and 0 lone pairs, resulting in sp^2 hybridization. In Al H ₄⁻ , the Al atom has 4 bond pairs and 0 lone pairs, resulting in sp^3 hybridization. Thus, there is a change in hybridization. In H ₂ O , the O atom has 2 bond pairs and 2 lone pairs, resulting in sp^3 hybridization. In H ₃ O ⁺ , the O atom has 3 bond pairs and 1 lone pair, resulting in sp^3 hybridization. No change occurs. In N H ₃ , the N atom has 3 bond pairs and 1 lone pair, resulting in sp^3 hybridizatio