Problem 37 - Chemistry: The Central Science

Question

Write the names of the following compounds, using the standard nomenclature rules for coordination complexes: (a) \(\left[\mathrm{Rh}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right] \mathrm{Cl}\) (b) \(\mathrm{K}_{2}\left[\mathrm{TiCl}_{6}\right]\) (c) \(\mathrm{MoOCl}_{4}\) (d) \(\left[\mathrm{Pt}\left(\mathrm{H}_{2} \mathrm{O}\right)_{4}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)\right] \mathrm{Br}_{2}\)

Step-by-Step Solution

Answer

(a) Tetrachloroammine rhodium(III) chloride (b) Potassium hexachlorotitanate(IV) (c) Tetrachlorooxomolybdenum(VI) (d) Tetraaqua oxalato platinum(IV) bromide

Step 1: Name the metal and assign oxidation state

For each compound, identify the central metal atom and assign its oxidation state. (a) Rh is the central metal atom and has an overall charge of +3 in this complex. The oxidation state of Rh is +3. (b) Ti is the central metal atom and has an overall charge of +4 in this complex. The oxidation state of Ti is +4. (c) Mo is the central metal atom and has an overall charge of +6 in this complex. The oxidation state of Mo is +6. (d) Pt is the central metal atom and has an overall charge of +4 in this complex. The oxidation state of Pt is +4.

Step 2: Name the ligands

For each complex, identify the ligands and name them using the appropriate conventions. (a) The ligands in this complex are \(\mathrm{NH}_{3}\)(ammine) and \(\mathrm{Cl}\)(chloro). (b) The ligand in this complex is \(\mathrm{Cl}\)(chloro). (c) The ligands in this complex are O (oxo) and Cl (chloro). (d) The ligands in this complex are \(\mathrm{H}_{2}\mathrm{O}\)(aqua) and \(\mathrm{C}_{2}\mathrm{O}_{4}\)(oxalato).

Step 3: Name the complexes with ligand names in alphabetical order

Arrange the ligand names in alphabetical order and then write the name of the metal. (a) Tetrachloroammine rhodium(III) ion (b) Hexachlorotitanate(IV) ion (c) Tetrachlorooxomolybdenum(VI) (d) Tetraaqua oxalato platinum(IV) ion

Step 4: Name the counter-ions or cations

For each complex, identify the counter-ions and cations and name them. (a) The counter-ion for this complex is \(\mathrm{Cl}\)(chloride). (b) The cation for this complex is \(\mathrm{K}\)(potassium). (d) The counter-ion for this complex is \(\mathrm{Br}\)(bromide).

Step 5: Combine the names of the complex, counter-ions, and cations

Combine the names from the previous steps to name the overall compounds. Include the counter-ions or cations as appropriate. (a) Tetrachloroammine rhodium(III) chloride (b) Potassium hexachlorotitanate(IV) (c) Tetrachlorooxomolybdenum(VI) (d) Tetraaqua oxalato platinum(IV) bromide