Which response gives the correct coordination number (C.N.) and oxidation number (O.N.) of the transition metal atom in [Co(NH₃)₂(H₂O)₂Cl₂]⁺ A) C.N. = 2; O.N. = +3 B) C.N. = 3; O.N. = +1 C) C.N. = 4; O.N. = +2 D) C.N. = 6; O.N. = +1 E) C.N. = 6; O.N. = +3

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Quizplus · Accepted Answer

The coordination number (C.N.) refers to the number of atoms directly bonded to the central metal atom. In this complex, cobalt (Co) is bonded to one nitrogen (from NH3), one oxygen (from H2O), and one chlorine (Cl), totaling three ligands. However, since NH3 is a monodentate ligand and H2O is also monodentate but Cl is counted as one, the total coordination number is incorrect in this interpretation. Correctly, NH3 and H2O are each monodentate, contributing one bond each, and Cl also contributes one bond, but the correct interpretation should consider all ligands presented, which seems to have been misinterpreted in the initial explanation. The correct coordination number should be based on the actual number of ligands and their denticity correctly interpreted from the formula, which typically would involve counting each ligand (NH3, H2O, Cl) once, leading to a typical coordination number for a complex of this nature being 6 if all positions are considered occupied in an octahedral arrangement, which is common for Co complexes.The oxidation number (O.N.) of the transition metal can be calculated by considering the charges of the ligands and the overall charge of the complex. Ammonia (NH3) is neutral, water (H2O) is neutral, and chloride (Cl) has a charge of -1. If the complex has a positive charge (as indicated by the notation at the end of the complex formula), and assuming the common charges for ligands, the oxidation state of Co must be calculated to balance the charges such that the overall charge of the complex is as indicated. Without the exact charges from the formula due to formatting, the typical approach would involve balancing the charges, where Co typically exhibits +2 or +3 in its complexes, with +3 being common in a complex with neutral and a single negative ligand to achieve a neutral or positively charged complex overall.The initial explanation mistakenly analyzed the ligands' contribution and their denticity, leading to an incorrect coordination number. The correct approach involves a detailed understanding of ligand denticity and the metal's oxidation state to balance the complex's overall charge, typically leading to a coordination number of 6 for octahedral complexes involving Co with a combination of neutral and charged ligands, and an oxidation state that balances the charge of the ligands.

Which Response Gives the Correct Coordination Number (C