Problem 78 - Chemistry An Atoms First Approach

Question

Name the following coordination compounds. a. \(\mathrm{Na}_{4}\left[\mathrm{Ni}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{3}\right]\) b. \(\mathrm{K}_{2}\left[\mathrm{CoCl}_{4}\right]\) c. \(\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{SO}_{4}\) d. \(\left[\mathrm{Co}(\mathrm{en})_{2}(\mathrm{SCN}) \mathrm{Cl}\right] \mathrm{Cl}\)

Step-by-Step Solution

Answer

The short answer for the given coordination compounds is: a. Tetrasodium trioxalatonickel(II) b. Dipotassium tetrachloridocobalt(II) c. Tetraamminecopper(II) sulfate d. Diethylenediamine thiocyanato chloridocobalt(III) chloride

Step 1: Identify the central metal atom/ion and ligands

In this compound, Ni is the central metal ion and three oxalate ligands (\(\mathrm{C}_{2}\mathrm{O}_{4}^{-2}\)) are surrounding it. There are 4 sodium ions (\(\mathrm{Na}^{+}\)) as counterions.

Step 2: Name the compound following IUPAC conventions

The name of the compound should follow the order: cation - anion - ligand - metal - oxidation state. We have: 1. Cation: tetrasodium 2. Ligand: trioxalato (since there are three oxalate ligands) 3. Metal: nickel 4. Oxidation state: (3 x (-2)) + (4 x 1) = 0; hence, oxidation state = 2. The full name is: Tetrasodium trioxalatonickel(II) #(b) \(\mathrm{K}_{2}\left[\mathrm{CoCl}_{4}\right]\):#

Step 3: Identify the central metal atom/ion and ligands

In this compound, Co is the central metal ion and there are 4 chloride ions (\(\mathrm{Cl}^{-}\)) surrounding it. There are 2 potassium ions (\(\mathrm{K}^+\)) as counterions.

Step 4: Name the compound following IUPAC conventions

The name of the compound should follow the order: cation - anion - ligand - metal - oxidation state. We have: 1. Cation: dipotassium 2. Ligand: tetrachlorido (since there are 4 chloride ligands) 3. Metal: cobalt 4. Oxidation state: (4 x (-1)) + (2 x 1) = 0; hence, oxidation state = 2. The full name is: Dipotassium tetrachloridocobalt(II) #(c) \(\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{SO}_{4}\):#

Step 5: Identify the central metal atom/ion and ligands

In this compound, Cu is the central metal ion and there are 4 ammonia ligands (\(\mathrm{NH}_{3}\)) surrounding it. The counterion is sulfate (\(\mathrm{SO}_{4}^{-2}\)).

Step 6: Name the compound following IUPAC conventions

The name of the compound should follow the order: cation - anion - ligand - metal - oxidation state. We have: 1. Cation: tetraammine (since there are 4 ammonia ligands) 2. Anion: sulfate 3. Metal: copper 4. Oxidation state: 0; hence, oxidation state = 2. The full name is: Tetraamminecopper(II) sulfate #(d) \(\left[\mathrm{Co}(\mathrm{en})_{2}(\mathrm{SCN}) \mathrm{Cl}\right] \mathrm{Cl}\):#

Step 7: Identify the central metal atom/ion and ligands

In this compound, Co is the central metal ion, and its ligands are 2 ethylenediamine ligands (en), one thiocyanate ligand (\(\mathrm{SCN}^{-}\)), and one chloride ion (\(\mathrm{Cl}^{-}\)). The counterion is one chloride ion.

Step 8: Name the compound following IUPAC conventions

The name of the compound should follow the order: cation - anion - ligand - metal - oxidation state. We have: 1. Cation: diethylenediamine (since there are 2 en ligands), thiochanato (follow alphabetical order) 2. Anion: chlorido 3. Metal: cobalt 4. Oxidation state: (1 x (-1)) + (1 x 1) = 0; hence, oxidation state = 3. The full name is: Diethylenediamine thiocyanato chloridocobalt(III) chloride