Chapter 9, Problem 9C.4E

(a)

Interpretation Introduction

Interpretation:

The chemical formula of the complex triamminediaquacobalt(II) hydroxide has to be given.

Concept Introduction:

Rules for writing the formula of the complex:

• Write the chemical symbol of the central atom (usually a metal atom) first, followed by symbols for the ligands, then enclose the entire collection of symbols between square brackets and add the overall charge.
• Write the chemical symbols of ligands in alphabetical order, when different ligands contain the same element, those denoted by a single letter (e.g., O) take priority over symbols represented by two or more letters (e.g., OH).  If a particular point needs to be emphasized, then the order may be varied.  For example water as a ligand is denoted OH2, to emphasize that the O links to the metal atom.
• To avoid any ambiguity, the linking atom can be underlined.

Answer to Problem 9C.4E

The chemical formula of the complex triamminediaquacobalt (II) hydroxide is $\left[\text{Co}{\left({\text{NH}}_{\text{3}}\right)}_3{\left({\text{H}}_{\text{2}}\text{O}\right)}_{\text{2}}\right]\text{OH}\text{.}$

Explanation of Solution

• Write the chemical symbol of the central cobalt $\left(\text{Co}\right)$ atom first, followed by symbols for the ligands then enclose the entire collection of symbols between square brackets and add the overall charge and write the chemical symbols of ligands in alphabetical order of their names.

The chemical formula of the complex triamminediaquacobalt (II) hydroxide is $\left[\text{Co}{\left({\text{NH}}_{\text{3}}\right)}_3{\left({\text{H}}_{\text{2}}\text{O}\right)}_{\text{2}}\right]\text{OH}\text{.}$

(b)

Interpretation Introduction

Interpretation:

The chemical formula of the complex dichloridobisethylenediamminecobalt (III) bromide has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 9C.4E

The chemical formula of the complex dichloridobisethylenediamminecobalt (III) bromide is $\left[\text{Co}{\left(\text{Cl}\right)}_{\text{2}}{\left(\text{en}\right)}_{\text{2}}\right]\text{Br}\text{.}$

Explanation of Solution

Write the chemical symbol of the central cobalt $\left(\text{Co}\right)$ atom first, followed by symbols for the ligands then enclose the entire collection of symbols between square brackets and add the overall charge and write the chemical symbols of ligands in alphabetical order of their names.

The chemical formula of the complex dichloridobisethylenediamminecobalt (III) bromide is $\left[\text{Co}{\left(\text{Cl}\right)}_{\text{2}}{\left(\text{en}\right)}_{\text{2}}\right]\text{Br}\text{.}$

(c)

Interpretation Introduction

Interpretation:

The chemical formula of the complex sodiumtriaminechloridonickelate(II) has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 9C.4E

The chemical formula of the complex sodiumtriaminechloridonickelate (II) is ${\text{Na}}_{\text{2}}{\left[\text{Ni}{\left({\text{NH}}_{\text{3}}\right)}_{\text{3}}\text{Cl}\right]}^{\text{2-}}\text{.}$

Explanation of Solution

• The cationic part of the complex has to be given first and then write the chemical symbol of the central atom first, followed by symbols for the ligands then enclose the entire collection of symbols between square brackets and add the overall charge and write the chemical symbols of ligands in alphabetical order of their names.  Since the overall charge of the complex is two there are two sodium ions.

The chemical formula of the complex sodiumtriaminechloridonickelate (II) is ${\text{Na}}_{\text{2}}{\left[\text{Ni}{\left({\text{NH}}_{\text{3}}\right)}_{\text{3}}\text{Cl}\right]}^{\text{2-}}\text{.}$

(d)

Interpretation Introduction

Interpretation:

The chemical formula of the complex barium(trioxalato)ferrate (III) has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 9C.4E

The chemical formula of the complex barium(trioxalato)ferrate (III) is ${\text{Ba}}_{\text{3}}{\left[\text{Fe}{\left(\text{ox}\right)}_{\text{3}}\right]}^{\text{3+}}\text{.}$

Explanation of Solution

• The cationic part of the complex has to be given first.  The symbol of the barium must written first.
• Write the chemical symbol of the central iron atom first, followed by symbols for the ligands then enclose the entire collection of symbols between square brackets and add the overall charge and write the chemical symbols of ligands in alphabetical order of their names.

The chemical formula of the complex barium(trioxalato)ferrate (III) is ${\text{Ba}}_{\text{3}}{\left[\text{Fe}{\left(\text{ox}\right)}_{\text{3}}\right]}^{\text{3+}}\text{.}$

(e)

Interpretation Introduction

Interpretation:

The chemical formula of the complex diaquadichloroplatinum(IV) iodide has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 9C.4E

The chemical formula of the complex diaquadichloroplatinum (IV) iodide is ${\left[\text{Pt}{\left({\text{H}}_{\text{2}}\text{O}\right)}_{\text{2}}\left(\text{Cl}\right)\right]}^{\text{3+}}{\text{I}}_{\text{3}}\text{.}$

Explanation of Solution

Write the chemical symbol of the central iron atom first, followed by symbols for the ligands then enclose the entire collection of symbols between square brackets and add the overall charge and write the chemical symbols of ligands in alphabetical order of their names.

The chemical formula of the complex diaquadichloroplatinum(IV) iodide is ${\left[\text{Pt}{\left({\text{H}}_{\text{2}}\text{O}\right)}_{\text{2}}\left(\text{Cl}\right)\right]}^{\text{3+}}{\text{I}}_{\text{3}}\text{.}$