In the formula [Cu(NH3)4]2+, what does the number 4 represent?

In the formula [Cu(NH3)4]2+, what does the number 4 represent?

• A. The oxidation number of Cu
• B. The number of NH3 ligands
• C. Both oxidation and coordination numbers
• D. Neither oxidation nor coordination numbers

Answer: (B)

In the formula [Cu(NH3)4]2+, the number 4 indicates the quantity of ammonia (NH3) ligands that are coordinated to the copper (Cu) ion. Each NH3 molecule is a neutral ligand that donates a pair of electrons to the central metal ion, forming coordinate covalent bonds. Coordination number refers to the number of ligands directly bonded to the central metal ion in a complex. In this case, the coordination number of Cu is 4, as it is surrounded by four NH3 ligands. The presence of the charge (2+) indicates the oxidation state of the copper ion, but the number itself does not represent that; rather, it strictly indicates how many NH3 molecules are involved in the complexation process. The other choices do not represent what is being asked in the context of the formula. The oxidation state itself is not represented by the 4, but rather by the entire charge of the complex, emphasizing the role of each component in coordination chemistry.

In the formula [Cu(NH3)4]2+, the number 4 indicates the quantity of ammonia (NH3) ligands that are coordinated to the copper (Cu) ion. Each NH3 molecule is a neutral ligand that donates a pair of electrons to the central metal ion, forming coordinate covalent bonds.

Coordination number refers to the number of ligands directly bonded to the central metal ion in a complex. In this case, the coordination number of Cu is 4, as it is surrounded by four NH3 ligands. The presence of the charge (2+) indicates the oxidation state of the copper ion, but the number itself does not represent that; rather, it strictly indicates how many NH3 molecules are involved in the complexation process.

The other choices do not represent what is being asked in the context of the formula. The oxidation state itself is not represented by the 4, but rather by the entire charge of the complex, emphasizing the role of each component in coordination chemistry.