Chapter 4, Problem 1QAP

Write the formulas of the following compounds and decide which are soluble in water.

(a) sodium sulfate

(b) iron(lll) nitrate

(c) silver chloride

(d) chromium(lll) hydroxide

Interpretation Introduction

(a)

Interpretation:

The formula for sodium sulfate should be written along with identify whether it is soluble in water or not.

Concept introduction:

First, the symbol of the metal (cation) with its ion charge as a superscript should be written.

The symbol of the non-metal (anion) with its ion charge or polyatomic ion as a superscript should be written.

After that, the charges should be crisscross so that they become subscript for the opposite element and + and - charges should be removed.

	${\text{NO}}_3^{-}$	${\mathrm{Cl}}^{-}$	${\text{SO}}_4^{2-}$	${\text{OH}}^{-}$	${\text{CO}}_3^{2-}$	${\text{PO}}_4^{3-}$
Group-1 cations and ${\text{NH}}_4^{+}$
Group-2 cations			${\text{BaSO}}_{\text{4}}$	$\text{Mg}{\left(\text{OH}\right)}_{\text{2}}$	-	-
Transitions metal cations ${\text{Pb}}^{2+}$, ${\text{Hg}}_2^{2+}$		$\text{AgCl}$ ${\text{PbCl}}_2$ ${\text{Hg}}_2{\text{Cl}}_2$	${\text{PbSO}}_{\text{4}}$ ${\text{Ag}}_2{\text{SO}}_{\text{4}}$	-	-	-

Solubility of any compound is predicted by above solubility chart.

Blank boxes indicate no precipitate formation occurs which means soluble in dilute solution.

Boxes with hyphen will form precipitate from dilute solutions and boxes where formula is written this is a cation-anion combination that will form precipitate.

Answer to Problem 1QAP

The formula is ${\text{Na}}_{\text{2}}{\text{SO}}_{\text{4}}$

It is soluble in water.

Explanation of Solution

Given compound is sodium sulfate

Symbol of sodium is $\text{Na}$

Symbol of sulfate is ${\text{SO}}_4$

Sodium belongs to group 1 and carries +1 charge.

Sulfate is a polyatomic ion carries -2 charge.

The symbol of sodium and sulfate is written with their charges and charges are crisscrossed.

Thus, the formula is ${\text{Na}}_{\text{2}}{\text{SO}}_{\text{4}}$

Ions present in the solution is ${\text{Na}}^{+}$ and ${\text{SO}}_4{}^{2-}$

According to solubility, attractive forces present between ion and ion is less than the water to ion. Thus, it is soluble in water.

Interpretation Introduction

(b)

Interpretation:

The formula for iron(III) nitrate should be written along with identify whether it is soluble in water or not.

Concept introduction:

First, the symbol of the metal (cation) with its ion charge as a superscript should be written.

The symbol of the non-metal (anion) with its ion charge or polyatomic ion as a superscript should be written.

After that, the charges should be crisscross so that they become subscript for the opposite element and + and - charges should be removed.

	${\text{NO}}_3^{-}$	${\mathrm{Cl}}^{-}$	${\text{SO}}_4^{2-}$	${\text{OH}}^{-}$	${\text{CO}}_3^{2-}$	${\text{PO}}_4^{3-}$
Group-1 cations and ${\text{NH}}_4^{+}$
Group-2 cations			${\text{BaSO}}_{\text{4}}$	$\text{Mg}{\left(\text{OH}\right)}_{\text{2}}$	-	-
Transitions metal cations ${\text{Pb}}^{2+}$, ${\text{Hg}}_2^{2+}$		$\text{AgCl}$ ${\text{PbCl}}_2$ ${\text{Hg}}_2{\text{Cl}}_2$	${\text{PbSO}}_{\text{4}}$ ${\text{Ag}}_2{\text{SO}}_{\text{4}}$	-	-	-

Solubility of any compound is predicted by above solubility chart.

Blank boxes indicate no precipitate formation occurs which means soluble in dilute solution.

Boxes with hyphen will form precipitate from dilute solutions and boxes where formula is written this is a cation-anion combination that will form precipitate.

Answer to Problem 1QAP

The formula is ${\text{Fe(NO}}_3{)}_3$

It is soluble in water.

Explanation of Solution

Given compound is iron(III) nitrate

Symbol of iron is $\text{Fe}$

Symbol of nitrate is ${\text{NO}}_3$

Here, iron(III) implies iron carries +3 charge.

Nitrate is a polyatomic ion carries -1 charge.

The symbol of iron and nitrate is written with their charges and charges are crisscrossed.

Thus, the formula is ${\text{Fe(NO}}_3{)}_3$

Ions present in the solution is ${\text{Fe}}^{+3}$ and ${\text{NO}}_3{}^{-}$

According to solubility chart, all nitrates are soluble. Thus, iron(III) nitrate is soluble in water.

Interpretation Introduction

(c)

Interpretation:

The formula for silver chloride should be written along with identify whether it is soluble in water or not.

Concept introduction:

First, the symbol of the metal (cation) with its ion charge as a superscript should be written.

The symbol of the non-metal (anion) with its ion charge or polyatomic ion as a superscript should be written.

After that, the charges should be crisscross so that they become subscript for the opposite element and + and - charges should be removed.

	${\text{NO}}_3^{-}$	${\mathrm{Cl}}^{-}$	${\text{SO}}_4^{2-}$	${\text{OH}}^{-}$	${\text{CO}}_3^{2-}$	${\text{PO}}_4^{3-}$
Group-1 cations and ${\text{NH}}_4^{+}$
Group-2 cations			${\text{BaSO}}_{\text{4}}$	$\text{Mg}{\left(\text{OH}\right)}_{\text{2}}$	-	-
Transitions metal cations ${\text{Pb}}^{2+}$, ${\text{Hg}}_2^{2+}$		$\text{AgCl}$ ${\text{PbCl}}_2$ ${\text{Hg}}_2{\text{Cl}}_2$	${\text{PbSO}}_{\text{4}}$ ${\text{Ag}}_2{\text{SO}}_{\text{4}}$	-	-	-

Solubility of any compound is predicted by above solubility chart.

Blank boxes indicate no precipitate formation occurs which means soluble in dilute solution.

Boxes with hyphen will form precipitate from dilute solutions and boxes where formula is written this is a cation-anion combination that will form precipitate.

Answer to Problem 1QAP

The formula is $\text{AgCl}$

It is insoluble in water.

Explanation of Solution

Given compound is silver chloride

Symbol of silver is $\text{Ag}$

Symbol of chloride is $\text{Cl}$

Here, silver is a metal carries + 1 charge.

Chloride is a non-metal carries -1 charge.

The symbol of silver and chloride is written with their charges and charges are crisscrossed.

The formula is ${\text{Ag}}_1{\text{Cl}}_{\text{1}}$

Make the above formula simplify, thus the formula of given compound is $\text{AgCl}$

Ions present in the solution is ${\text{Ag}}^{+1}$ and ${\text{Cl}}^{-}$

According to the solubility chart, it will form precipitate, thus insoluble in water.

Interpretation Introduction

(d)

Interpretation:

The formula for chromium(III) hydroxide should be written along with identify whether it is soluble in water or not.

Concept introduction:

First, the symbol of the metal (cation) with its ion charge as a superscript should be written.

The symbol of the non-metal (anion) with its ion charge or polyatomic ion as a superscript should be written.

After that, the charges should be crisscross so that they become subscript for the opposite element and + and - charges should be removed.

	${\text{NO}}_3^{-}$	${\mathrm{Cl}}^{-}$	${\text{SO}}_4^{2-}$	${\text{OH}}^{-}$	${\text{CO}}_3^{2-}$	${\text{PO}}_4^{3-}$
Group-1 cations and ${\text{NH}}_4^{+}$
Group-2 cations			${\text{BaSO}}_{\text{4}}$	$\text{Mg}{\left(\text{OH}\right)}_{\text{2}}$	-	-
Transitions metal cations ${\text{Pb}}^{2+}$, ${\text{Hg}}_2^{2+}$		$\text{AgCl}$ ${\text{PbCl}}_2$ ${\text{Hg}}_2{\text{Cl}}_2$	${\text{PbSO}}_{\text{4}}$ ${\text{Ag}}_2{\text{SO}}_{\text{4}}$	-	-	-

Solubility of any compound is predicted by above solubility chart.

Blank boxes indicate no precipitate formation occurs which means soluble in dilute solution.

Boxes with hyphen will form precipitate from dilute solutions and boxes where formula is written this is a cation-anion combination that will form precipitate.

Answer to Problem 1QAP

The formula is ${\text{Cr(OH)}}_3$

It is insoluble in water.

Explanation of Solution

Given compound is chromium(III) hydroxide

Symbol of chromium is $\text{Cr}$

Symbol of hydroxide is $\text{OH}$

Here, chromium(III) implieschromium carries +3 charge.

Hydroxide ion carries -1 charge.

The symbol of chromium and hydroxide is written with their charges and charges are crisscrossed.

The formula is ${\text{Cr(OH)}}_3$

Ions present in the solution is ${\text{Cr}}^{+3}$ and ${\text{OH}}^{-}$

According to the solubility chart, it will form precipitate, thus insoluble in water.