Question

Give formulas for the following complex ions. a. tetrachloroferrate(III) ion b. pentaammineaquaruthenium(III) ion c. tetracarbonyldihydroxochromium(III) ion d. amminetrichloroplatinate(II) ion

Short answer

a. $$[FeC{l}_4{]}^{3-}$$ b. $$[Ru(N{H}_3{)}_5{H}_{2}O{]}^{3+}$$ c. $$[Cr(CO{)}_4(OH{)}_2{]}^{3-}$$ d. $$[Pt(N{H}_3)C{l}_3{]}^{2-}$$

Step-by-step solution

Identify the central metal atom and its oxidation state

For each complex ion, identify the central metal atom and its oxidation state (the Roman numeral in parentheses). To do this, look for the metal element in the name and note the number in parentheses, which indicates the oxidation state. a. tetrachloroferrate(III) ion The central metal atom is iron (Fe) and its oxidation state is +3. b. pentaammineaquaruthenium(III) ion The central metal atom is ruthenium (Ru) and its oxidation state is +3. c. tetracarbonyldihydroxochromium(III) ion The central metal atom is chromium (Cr) and its oxidation state is +3. d. amminetrichloroplatinate(II) ion The central metal atom is platinum (Pt) and its oxidation state is +2.

Identify the ligands and their corresponding symbols

For each complex ion, identify the ligands and their corresponding symbols. a. tetrachloroferrate(III) ion The ligand is chloro, and its corresponding symbol is Cl^-. b. pentaammineaquaruthenium(III) ion The ligands are ammine and aqua, with corresponding symbols NH3 and H2O. c. tetracarbonyldihydroxochromium(III) ion The ligands are carbonyl and hydroxo, with corresponding symbols CO and OH^-. d. amminetrichloroplatinate(II) ion The ligands are ammine and chloro, with corresponding symbols NH3 and Cl^-.

Write the formulas for each complex ion

Now that we have identified the central metal atoms, their oxidation states, and the ligands, we can write the formulas for each complex ion. Remember to write the ligands in alphabetical order, disregarding any numerical prefixes. a. tetrachloroferrate(III) ion The formula is $$[FeC{l}_4{]}^{3-}$$ b. pentaammineaquaruthenium(III) ion The formula is $$[Ru(N{H}_3{)}_5{H}_{2}O{]}^{3+}$$ c. tetracarbonyldihydroxochromium(III) ion The formula is $$[Cr(CO{)}_4(OH{)}_2{]}^{3-}$$ d. amminetrichloroplatinate(II) ion The formula is $$[Pt(N{H}_3)C{l}_3{]}^{2-}$$