Chapter 9, Problem 106A

(a)

Interpretation Introduction

Interpretation: The compounds calcium carbonate and potassium carbonate are to be distinguished and analyzed.

Concept Introduction: A compound is defined as the formation of two or many elements in any proportion. It is a pure substance. The property of compounds will differ when compared with the property of their constituent elements.

Answer to Problem 106A

The compounds potassium carbonate and calcium carbonate can be distinguished by a water dissolution test.

Explanation of Solution

Potassium carbonate is soluble in water whereas calcium carbonate is very less soluble in water.

So, a water dissolution test can be performed by adding the compound to water and stirring.

Potassium carbonate will be dissolved rapidly whereas calcium carbonate remains undissolved in water.

(b)

Interpretation Introduction

Interpretation: The samples of copper(II) sulfate pentahydrate and iron(II) sulfate pentahydrate are to be distinguished.

Concept Introduction: A compound is defined as the formation of two or many elements in any proportion. It is a pure substance. The property of compounds will differ when compared with the property of their constituent elements.

Answer to Problem 106A

The samples of copper(II) sulfate pentahydrate and iron(II) sulfate pentahydrate are distinguished with the help of their appearance.

Explanation of Solution

The samples of copper (II) sulfate pentahydrate and iron (II) sulfate pentahydrate are distinguished with the help of their appearance.

Copper (II) sulfate pentahydrate is blue in color while iron (II) sulfate pentahydrate is green in color.

(c)

Interpretation Introduction

Interpretation: A mixture of ammonium chloride and barium sulfate is to be separated.

Concept Introduction: A compound is defined as the formation of two or many elements in any proportion. It is a pure substance. The property of compounds will differ when compared with the property of their constituent elements.

Answer to Problem 106A

A mixture of ammonium chloride and barium sulfate is separated by heating the mixture since they differ in melting point.

Explanation of Solution

Barium sulfate and ammonium chloride are separated using two different methods. They both differ in melting point and solubility of water.

Ammonium chloride is highly soluble in water whereas barium sulfate is very less soluble in water.

But in the mixture, it is difficult to separate the compounds.

The separation of the mixture can be done by heating the mixture.

Since ammonium chloride has a lower melting point, on heating up the mixture it goes to a liquid state whereas barium sulfate will remain in the solid state.

(c)

Interpretation Introduction

Interpretation: The elements in the table in order of increasing density are to be listed. The elements as metals or nonmetals are to be identified.

Concept Introduction: The mass of a substance per unit of volume is known as its density. The elements are classified based on their chemical properties. The classification of elements are metals, non-metals, and metalloids.

Answer to Problem 106A

The elements in the table in increasing order of density are chlorine, sulfur, bromine, barium, iodine, and mercury.

Chlorine, sulfur, bromine, and iodine are non-metals.

The metals are mercury and barium.

Explanation of Solution

Barium, chlorine, iodine, mercury, sulfur, and mercury are the elements found in the table.

Ammonium chloride, barium sulfate, calcium carbonate, copper (II) sulfate pentahydrate, iron (II) sulfate pentahydrate, and potassium carbonate are the compounds in the table.

Chlorine, sulfur, bromine, and iodine are non-metals.

The metals are mercury and barium.

The increasing order of density is chlorine, sulfur, bromine, barium, iodine, and mercury.

Chlorine has the least density while mercury has the highest density.

(d)

Interpretation Introduction

Interpretation: The compounds in the table in order of decreasing density are to be listed.

Concept Introduction: The mass of a substance per unit of volume is known as its density. A compound is defined as the formation of two or many elements in any proportion. It is a pure substance.

Answer to Problem 106A

The compounds in the table in order of decreasing density are barium sulfate, calcium carbonate, potassium carbonate, copper (II) sulfate pentahydrate, iron (II) sulfate pentahydrate, and ammonium chloride.

Explanation of Solution

Barium, chlorine, iodine, mercury, sulfur, and mercury are the elements found in the table.

Ammonium chloride, barium sulfate, calcium carbonate, copper (II) sulfate pentahydrate, iron (II) sulfate pentahydrate, and potassium carbonate are the compounds in the table.

The decreasing order of density of compounds is barium sulfate, calcium carbonate, potassium carbonate, copper (II) sulfate pentahydrate, iron (II) sulfate pentahydrate, and ammonium chloride.

Ammonium chloride has the least density while barium sulfate has the highest density.

(e)

Interpretation Introduction

Interpretation: The mass of mercury is to be calculated.

Concept Introduction: The mass of a substance per unit of volume is known as its density. The formula of density is given as follows:

  $\text{density =}\frac{\text{mass}}{\text{volume}}$   ...... (1)

Answer to Problem 106A

The mass of mercury is $639.2\text{g}$ .

Explanation of Solution

From the table, the density of mercury is $\text{13}\text{.6}{\text{g/cm}}^3$ .

The volume of mercury is $\text{47}{\text{cm}}^3$ .

To calculate the mass of mercury, substitute the values in equation (1) as follows:

  $\begin{array}{c}\text{density =}\frac{\text{mass}}{\text{volume}}\\ \text{mass = density×volume}\\ =13.6{\text{g/cm}}^3\times 47{\text{cm}}^3\\ =639.2\text{g}\end{array}$

(f)

Interpretation Introduction

Interpretation: The volume of sulfur is to be calculated.

Concept Introduction: The mass of a substance per unit of volume is known as its density. The formula of density is given as follows:

  $\text{density =}\frac{\text{mass}}{\text{volume}}$   ...... (1)

Answer to Problem 106A

The volume of sulfur is $7.9{\text{cm}}^3$ .

Explanation of Solution

From the table, the density of sulfur is $2.1{\text{g/cm}}^3$ .

The mass of sulfur is $16.6\text{g}$ .

To calculate the volume of sulfur, substitute the values in equation (1) as follows:

  $\begin{array}{c}\text{density =}\frac{\text{mass}}{\text{volume}}\\ \text{volume = }\frac{\text{mass}}{\text{density}}\\ =\frac{16.6\text{g}}{2.1{\text{g/cm}}^3}\\ =7.9{\text{cm}}^3\end{array}$

(g)

Interpretation Introduction

Interpretation: The elements in Group 7A listed in the table are to be distinguished.

Concept Introduction: Element is the simple form of matter. The particles of an element consisting of only one type of atom. These particles can exist as atoms or molecules.

Answer to Problem 106A

The group 7A elements in the table are distinguished with the help of their appearance (color).

Explanation of Solution

The group 7A elements are the halogens.

The halogens present in the table are iodine, chlorine, and bromine.

They are easy to distinguish.

They differ in their appearance at atmospheric pressure and room temperature.

Bromine is a brownish-red liquid, chlorine is a yellow-green gas and iodine is a black crystalline solid.