Chapter 8, Problem 139A

Interpretation Introduction

(a)

Interpretation:

The chemical formula of calcium carbonate is to be written.

Concept introduction:

In the molecular formula, the element symbols and the subscripts number tells the type and the number of each atom in a molecule.

Answer to Problem 139A

The chemical formula of calcium carbonate is ${\text{CaCO}}_3$.

Explanation of Solution

The “calcium carbonate” is an ionic solid which is made up of calcium ion $\left({\text{Ca}}^{2+}\right)$ and carbonate ion $\left({\text{CO}}_3^{2-}\right)$. The calcium ion has two positive charges and carbonate ion has two negative charges. Therefore, to obtain neutral compound, 1:1 ratio of calcium ion $\left({\text{Ca}}^{2+}\right)$ and carbonate ion $\left({\text{CO}}_3^{2-}\right)$ is required. Therefore, the chemical formula of “calcium carbonate” is ${\text{CaCO}}_3$.

Interpretation Introduction

(b)

Interpretation:

The chemical formula of potassium chlorate is to be written.

Concept introduction:

In the molecular formula, the element symbols and the subscripts number tells the type and the number of each atom in a molecule.

Answer to Problem 139A

The chemical formula of potassium chlorate is ${\text{KClO}}_{\text{3}}$.

Explanation of Solution

The “potassium chlorate” is an ionic compound which is made up of potassium ion $\left({\text{K}}^{+}\right)$ and chlorate ion $\left({\text{ClO}}_3^{-}\right)$. The potassium ion has one positive charge and chlorate ion has one negative charge. Therefore, to obtain neutral compound, 1:1 ratio of potassium ion $\left({\text{K}}^{+}\right)$ and chlorate ion $\left({\text{ClO}}_3^{-}\right)$ is required. Therefore, the chemical formula of “potassium chlorate” is ${\text{KClO}}_{\text{3}}$.

Interpretation Introduction

(c)

Interpretation:

The chemical formula of silver acetate is to be written.

Concept introduction:

In the molecular formula, the element symbols and the subscripts number tells the type and the number of each atom in a molecule.

Answer to Problem 139A

The chemical formula of silver acetate is ${\text{AgC}}_2{\text{H}}_3{\text{O}}_{\text{2}}$.

Explanation of Solution

The “silver acetate” is an ionic compound which is made up of silver ion $\left({\text{Ag}}^{+}\right)$ and acetate ion $\left({\text{C}}_2{\text{H}}_3{\text{O}}_2^{-}\right)$. The silver ion has one positive charge and acetate ion has one negative charge. Therefore, to obtain neutral compound, 1:1 ratio of silver ion $\left({\text{Ag}}^{+}\right)$ and acetate ion $\left({\text{C}}_2{\text{H}}_3{\text{O}}_2^{-}\right)$ is required. Therefore, the chemical formula of “silver acetate” is ${\text{AgC}}_2{\text{H}}_3{\text{O}}_{\text{2}}$.

Interpretation Introduction

(d)

Interpretation:

The chemical formula of copper (II) sulfate is to be written.

Concept introduction:

In the molecular formula, the element symbols and the subscripts number tells the type and the number of each atom in a molecule.

Answer to Problem 139A

The chemical formula of copper (II) sulfate is ${\text{CuSO}}_4$.

Explanation of Solution

The “copper (II) sulfate” is an ionic solid which is made up of copper ion $\left({\text{Cu}}^{2+}\right)$ and sulfate ion $\left({\text{SO}}_4^{2-}\right)$. The calcium ion has two positive charges and carbonate ion has two negative charges. Therefore, to obtain neutral compound, 1:1 ratio of copper ion $\left({\text{Cu}}^{2+}\right)$ and sulfate ion $\left({\text{SO}}_4^{2-}\right)$ is required. Therefore, the chemical formula of “copper (II) sulfate” is ${\text{CuSO}}_4$.

Interpretation Introduction

(e)

Interpretation:

The chemical formula of ammonium phosphate is to be written.

Concept introduction:

In the molecular formula, the element symbols and the subscripts number tells the type and the number of each atom in a molecule.

Answer to Problem 139A

The chemical formula of ammonium phosphate is ${\left({\text{NH}}_4\right)}_{\text{3}}{\text{PO}}_4$.

Explanation of Solution

The “ammonium phosphate” is an ionic solid which is made up of ammonium ion $\left({\text{NH}}_4^{+}\right)$ and phosphate ion $\left({\text{PO}}_4^{3-}\right)$. The ammonium ion has one positive charge and phosphate ion has three negative charges. Therefore, to obtain neutral compound, 3:1 ratio of ammonium ion $\left({\text{NH}}_4^{+}\right)$ and phosphate ion $\left({\text{PO}}_4^{3-}\right)$ is required. Therefore, the chemical formula of “ammonium phosphate” is ${\left({\text{NH}}_4\right)}_{\text{3}}{\text{PO}}_4$.