Chapter 8, Problem 12A

(a)

Interpretation Introduction

Interpretation: The molecular equation for the precipitation reaction between given aqueous solutions need to be determined. The formula of precipitate needs to be underlined if formed.

Concept Introduction: The ability of the solute, to dissolve in solvent is known as solubility. Solubility rules are proposed for different ions, whether they are soluble or not. According to solubility rule, it will be confirm that given salt solution will form precipitate or remain aqueous.

Explanation of Solution

The given aqueous solutions are nitric acid and barium chloride.

The reaction is represented as follows:

  ${\text{BaCl}}_{\text{2}}\left(aq\right){\text{+2HNO}}_{\text{3}}\left(aq\right)\to \text{Ba}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(aq\right)\text{+2HCl}\left(g\right)$

Salt containing nitrates (NO₃)^- are generally soluble.

Thus, BaCl₂ react with nitric acid and forms Ba(NO₃)₂ which is in soluble form.

(b)

Interpretation Introduction

Interpretation: The molecular equation for the precipitation reaction between given aqueous solutions need to be determined. The formula of precipitate needs to be underlined if formed.

Concept Introduction: The ability of the solute, to dissolve in solvent is known as solubility. Solubility rules are proposed for different ions, whether they are soluble or not. According to solubility rule, it will be confirm that given salt solution will form precipitate or remain aqueous.

Explanation of Solution

The given aqueous solutions are calcium chloride and potassium carbonate.

The reaction is represented as follows:

  ${\left({\text{NH}}_{\text{4}}\right)}_{\text{2}}\text{S}\left(aq\right){\text{+CoCl}}_{\text{2}}\left(aq\right)\to {\text{NH}}_{\text{4}}\text{Cl}\left(aq\right)\text{+}\underset{\_}{\text{CoS}\left(s\right)}$

Most sulphides of transition metals are highly insoluble.

Thus, ammonium sulphide on reaction with cobalt chloride forms an insoluble cobalt sulphide.

(c)

Interpretation Introduction

Interpretation: The molecular equation for the precipitation reaction between given aqueous solutions need to be determined. The formula of precipitate needs to be underlined if formed.

Concept Introduction: The ability of the solute, to dissolve in solvent is known as solubility. Solubility rules are proposed for different ions, whether they are soluble or not. According to solubility rule, it will be confirm that given salt solution will form precipitate or remain aqueous.

Explanation of Solution

The given aqueous solutions are sulphuric acid and lead (II) nitrate.

The reaction is represented as follows:

  $\text{Pb}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(aq\right){\text{+H}}_{\text{2}}{\text{SO}}_{\text{4}}\left(aq\right)\to \underset{\_}{{\text{PbSO}}_{\text{4}}\left(s\right)}{\text{+2HNO}}_{\text{3}}\left(aq\right)$

According to the solubility rule, most sulphates salts are soluble except CaSO₄, PbSO₄, BaSO₄.

Thus, lead nitrate reacts with Sulphuric acid to form an insoluble sulphate.

(d)

Interpretation Introduction

Interpretation: The molecular equation for the precipitation reaction between given aqueous solutions need to be determined. The formula of precipitate needs to be underlined if formed.

Concept Introduction: The ability of the solute, to dissolve in solvent is known as solubility. Solubility rules are proposed for different ions, whether they are soluble or not. According to solubility rule, it will be confirm that given salt solution will form precipitate or remain aqueous.

Explanation of Solution

The given aqueous solutions are calcium chloride and potassium carbonate.

The given reaction is as follows:

  ${\text{CaCl}}_{\text{2}}\left(aq\right){\text{+K}}_{\text{2}}{\text{CO}}_{\text{3}}\left(aq\right)\to \underset{\_}{{\text{CaCO}}_{\text{3}}\left(s\right)}\text{+2KCl}\left(aq\right)$

Carbonates are frequently insoluble. Moreover, group II carbonates (CaCO₃, SrCO₃ and BaCO₃) are insoluble.

Thus, potassium carbonate reacts with calcium chloride and forms an insoluble calcium carbonate.

(e)

Interpretation Introduction

Interpretation: The molecular equation for the precipitation reaction between given aqueous solutions need to be determined. The formula of precipitate needs to be underlined if formed.

Concept Introduction: The ability of the solute, to dissolve in solvent is known as solubility. Solubility rules are proposed for different ions, whether they are soluble or not. According to solubility rule, it will be confirm that given salt solution will form precipitate or remain aqueous.

Explanation of Solution

The given aqueous solutions are sodium acetate and ammonium nitrate.

The given reaction is as follows:

  ${\text{CH}}_{\text{3}}\text{COONa}\left(aq\right){\text{+NH}}_{\text{4}}{\text{NO}}_{\text{3}}\left(aq\right)\to {\text{CH}}_{\text{3}}\text{COOH}\left(aq\right){\text{+NH}}_{\text{3}}\left(aq\right){\text{+NaNO}}_{\text{3}}\left(aq\right)$

Here, NH₄+ and NO₃- definitely dissociate. NH₄+ is an acid, acetate is a base. Acetate can take one of ammonium’s protons to get acetic acid and ammonia. Thus, no precipitate is formed.

(f)

Interpretation Introduction

Interpretation: The molecular equation for the precipitation reaction between given aqueous solutions need to be determined. The formula of precipitate needs to be underlined if formed.

Concept Introduction: The ability of the solute, to dissolve in solvent is known as solubility. Solubility rules are proposed for different ions, whether they are soluble or not. According to solubility rule, it will be confirm that given salt solution will form precipitate or remain aqueous.

Explanation of Solution

The given aqueous solutions are sodium phosphate and chromium (III) chloride.

The given reaction is as follows:

Sodium phosphate reacts with chromium chloride and as a product forms an insoluble phosphate.

  ${\text{Na}}_{\text{3}}{\text{PO}}_{\text{4}}\left(aq\right){\text{+CrCl}}_{\text{3}}\left(aq\right)\to \underset{\_}{{\text{CrPO}}_{\text{4}}\left(s\right)}\text{+3NaCl}\left(aq\right)$