"Hybridisation of central atom does not always change due to back bonding". This statement is valid — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Examine the Lewis structures of the given molecules. Step 2: In PH_4^+, phosphorus donates a lone pair to H^+, forming a coordinate bond. In NO_2, nitrogen forms coordinate/dative-like bonds to oxygen to avoid exceeding its octet. In O_3, the central oxygen atom forms a coordinate covalent bond to one of the terminal oxygens. In CO_3^2- (carbonate), the central carbon forms three normal covalent sigma bonds and one pi bond, with negative charges residing on two oxygen atoms, meaning no coordinate bond is present. Step 3: Consequently, the carbonate ion (CO_3^2-) does not have any coordinate bonds, matching option (d).