Chapter 2, Problem 2.135P

(a)

Interpretation Introduction

Interpretation:

The coloured boxes that represent four non-metal elements are to be identified.

Concept introduction:

The periodic table is an arrangement of elements according to their properties, atomic number, and electronic configurations.

The characteristic properties of non-metals are as follows:

1. Non-metals, unlike metals, can be solid, liquid or gas.

2. Non-metal oxides are acidic in nature.

3. Non-metals are poor conductors of heat and electricity.

4. Non-metals have a tendency to gain electrons to form anions.

5. Non-metals are non-malleable.

6. Non-metals are not ductile.

7. Non-metals do not exhibit sonority.

Answer to Problem 2.135P

The four non-metal elements are represented by the black, red, green and purple boxes.

Explanation of Solution

In the periodic table, the non-metal elements are placed at the small upper-right portion. The coloured boxes present in the small upper-right region are red, black, green and purple. Hence, these coloured boxes represent the four non-metal elements.

Conclusion

The four non-metal elements are represented by the black, red, green and purple boxes.

(b)

Interpretation Introduction

Interpretation:

The coloured boxes that represent two metal elements are to be identified.

Concept introduction:

The periodic table is an arrangement of elements according to their properties, atomic number, and electronic configurations.

The characteristic properties of metals are as follows:

1. Metals are hard and shiny in appearance. Except for mercury, all metals are solid.

2. Metallic oxides are basic in nature.

3. Metals are good conductors of heat and electricity

4. Metals have a tendency to lose electrons to form cations.

5. Metals are malleable. They can be beaten into thin sheets

6. Metals are ductile. They can be drawn into wires.

7. Metals exhibit sonority.

Answer to Problem 2.135P

The two metal elements are represented by the brown and blue boxes.

Explanation of Solution

In the periodic table, the metal elements are placed at the large lower-left portion. The coloured boxes present in the large lower-left region are brown and blue. Hence, these coloured boxes represent the two metal elements.

Conclusion

The two metal elements are represented by the brown and blue boxes.

(c)

Interpretation Introduction

Interpretation:

The coloured boxes that represent three elements that are gaseous at room temperature are to be identified.

Concept introduction:

A periodic table is an arrangement of elements based on their atomic number, properties and electronic configuration. The table is arranged into groups and periods. The elements which are metallic in nature, occupy the large lower-left portion of the table. The non-metals occupy the small upper-right portion of the table. Metalloids like along the staircase line. Elements which appear in the same group have similar behaviour.

Answer to Problem 2.135P

The three elements that are gaseous at room temperature are represented by the red, green and purple boxes.

Explanation of Solution

All metals except mercury are solid at room temperature. The non-metal elements can be soft solids, liquids or gases. The non-metal elements are represented by the black, red green and purple boxes. The black box represents the element of carbon. Carbon is a solid element. The red, green and purple boxes represent the elements oxygen, chlorine and argon. At room temperature, oxygen, chlorine and argon exist in the gaseous form. Therefore, the red, green and purple boxes represent the elements that are gaseous at room temperature.

Conclusion

The three elements that are gaseous at room temperature are represented by the red, green and purple boxes.

(d)

Interpretation Introduction

Interpretation:

The coloured boxes that represent three elements that are solid at room temperature are to be identified.

Concept introduction:

A periodic table is an arrangement of elements based on their atomic number, properties and electronic configuration. The table is arranged into groups and periods. The elements which are metallic in nature, occupy the large lower-left portion of the table. The non-metals occupy the small upper-right portion of the table. Metalloids like along the staircase line. Elements which appear in the same group have similar behaviour.

Answer to Problem 2.135P

The three elements that are solid at room temperature are represented by the brown, blue and black boxes.

Explanation of Solution

All metals except mercury are solid at room temperature. Non-metals can be soft solids, liquids or gases. Metals are represented by the brown and blue boxes. The black box represents the carbon element. Carbon is a solid non-metal element. The red, green and purple boxes represent the elements oxygen, chlorine and argon. At room temperature, oxygen, chlorine and argon exist in the gaseous form. Therefore, the brown, blue and black boxes represent the elements that are solid at room temperature.

Conclusion

The three elements that are solid at room temperature are represented by the brown, blue and black boxes.

(e)

Interpretation Introduction

Interpretation:

A pair of elements that will form a covalent compound is to be determined.

Concept introduction:

Covalent compounds are formed by the interaction of two or more non-metal elements. In covalent compounds, the covalent bonds are formed by the sharing of electrons between the atoms instead of their transfer from one atom to another.

Answer to Problem 2.135P

Pair of elements that will form covalent compounds are red and black.

Explanation of Solution

An interaction between metals and non-metals leads to the formation of ionic bonds. The metal elements are represented by the brown and blue boxes. Hence the elements in the brown and blue boxes will not engage in covalent bonding. The non-metal elements are represented by the red, green, black and purple boxes. The purple box represents the noble gas argon. Argon is very stable and therefore, does not engage in compound formation. Hence, the only elements that engage in covalent bonding are represented by the red, green and black boxes.

The red and the black box elements are oxygen and carbon respectively. Carbon and oxygen can engage in multiple proportions $\left(\text{CO},{\text{CO}}_2\right)$ to form covalent compounds.

Conclusion

Pair of elements that will form covalent compounds are red and black.

(f)

Interpretation Introduction

Interpretation:

Another pair of elements that will likely form covalent compounds is to be determined.

Concept introduction:

Covalent compounds are formed by the interaction of two or more non-metal elements. In covalent compounds, the covalent bonds are formed by the sharing of electrons between the atoms instead of their transfer from one atom to another.

Answer to Problem 2.135P

Another pair of elements that will likely form covalent compounds are represented by the red and green boxes.

Explanation of Solution

The non-metal elements are represented by the red, green, black and purple boxes. The purple box represents the noble gas argon. Argon is very stable and therefore, does not engage in compound formation. Hence, the only elements that engage in covalent bonding are represented by the red, green and black boxes.

Apart from the pair of red and black box elements, the elements in the red and green boxes can also engage in covalent compound formation. The red box represents the element oxygen whereas the green box represents the element chlorine. Oxygen and chlorine can engage in multiple proportions $\left({\text{Cl}}_2\text{O},{\text{Cl}}_2{\text{O}}_2,{\text{Cl}}_2{\text{O}}_6\text{ etc}\right)$ to form covalent compounds.

Conclusion

Another pair of elements that will likely form covalent compounds are represented by the red and green boxes.

(g)

Interpretation Introduction

Interpretation:

The coloured boxes that represent a pair of elements that will likely form an ionic compound with the formula $\text{MX}$ are to be determined.

Concept introduction:

Ionic compounds are formed by the interaction of metal elements with non-metal elements. In an ionic bond formation, there is a transfer of electrons between atoms. The metal elements have a tendency to lose electrons in order to gain stability, whereas non-metals acquire stability by gaining the electrons. The ions thus formed attract each other due to strong electrostatic force between them to form ionic compounds.

Answer to Problem 2.135P

One of the pairs of the elements that will likely form ionic compounds is represented by the brown and green boxes.

Explanation of Solution

Ionic compounds are formed by the interaction of metals with non-metals. The element represented by the brown box is sodium $\left(\text{Na}\right)$ whereas the green box represents the element chlorine $\left(\text{Cl}\right)$. The compound represented by the formula $\text{MX}$ must have two elements in a $1:1$ ratio.

Sodium and chloride ions form ionic compound $\text{NaCl}$ as follows:

${\text{Na}}^{+}+{\text{Cl}}^{-}\to \text{NaCl}$

In the compound $\text{NaCl}$, the sodium and the chloride ions are present in the $1:1$ ratio and have equal and opposite charges $\left(+1\text{ and }-1\right)$ on them.

Conclusion

One of the pairs of the elements that will likely form ionic compounds is represented by the brown and green boxes.

(h)

Interpretation Introduction

Interpretation:

The coloured boxes that represent another pair of elements that will likely form an ionic compound with the formula $\text{MX}$ are to be determined.

Concept introduction:

Ionic compounds are formed by the interaction of metal elements with non-metal elements. In an ionic bond formation, there is a transfer of electrons between atoms. The metal elements have a tendency to lose electrons in order to gain stability, whereas non-metals acquire stability by gaining the electrons. The ions thus formed attract each other due to strong electrostatic force between them to form ionic compounds.

Answer to Problem 2.135P

The coloured boxes that represent another pair of elements that will form an ionic compound with the formula $\text{MX}$ are blue and red.

Explanation of Solution

The coloured boxes red and blue represent the elements of oxygen and barium respectively. The ionization of oxygen and barium lead to the formation of oxide and barium ions $\left({\text{O}}^{2-}{\text{ and Ba}}^{2+}\right)$. The barium and the oxide ions have equal and opposite charges on them. Therefore barium and oxide ions combine in a $1:1$ ratio to form an ionic compound $\text{BaO}$ with the formula $\text{MX}$ as follows:

${\text{Ba}}^{2+}+{\text{O}}^{2-}\to \text{BaO}$

Conclusion

The coloured boxes that represent another pair of elements that will form an ionic compound are blue and red.

(i)

Interpretation Introduction

Interpretation:

The coloured boxes that represent a pair of elements that will likely form an ionic compound with the formula ${\text{M}}_2\text{X}$ are to be determined.

Concept introduction:

Ionic compounds are formed by the interaction of metal elements with non-metal elements. In an ionic bond formation, there is a transfer of electrons between atoms. The metal elements have a tendency to lose electrons in order to gain stability, whereas non-metals acquire stability by gaining the electrons. The ions thus formed attract each other due to strong electrostatic force between them to form ionic compounds.

Answer to Problem 2.135P

The coloured boxes that represent the elements that will form an ionic compound with the formula ${\text{M}}_2\text{X}$ are brown and red.

Explanation of Solution

For an ionic compound to have a formula of ${\text{M}}_2\text{X}$, the metal element must combine with the non-metal element in a $2:1$ ratio. The charge on the metal must be half the charge on the non-metal element in order to have a $2:1$ ratio between them.

The brown and the red boxes represent the elements sodium and oxygen respectively. Sodium and oxygen ionize to form ${\text{Na}}^{+}$ and ${\text{O}}^{2-}$ ions. The charge on the sodium ion is $+1$ whereas the charge on the oxide ion is $-2$. In order to balance the charge on the oxide ion, two sodium ions must combine with one oxide ion in a $2:1$ ratio as follows:

$2{\text{Na}}^{+}+{\text{O}}^{2-}\to {\text{Na}}_2\text{O}$

Conclusion

The coloured boxes that represent the elements that will form an ionic compound with the formula ${\text{M}}_2\text{X}$ are brown and red.

(j)

Interpretation Introduction

Interpretation:

The coloured boxes that represent a pair of elements that will likely form an ionic compound with the formula ${\text{MX}}_2$ are to be determined.

Concept introduction:

Ionic compounds are formed by the interaction of metal elements with non-metal elements. In an ionic bond formation, there is a transfer of electrons between atoms. The metal elements have a tendency to lose electrons in order to gain stability, whereas non-metals acquire stability by gaining the electrons. The ions thus formed attract each other due to strong electrostatic force between them to form ionic compounds.

Answer to Problem 2.135P

The coloured boxes that represent the elements that will form an ionic compound with the formula ${\text{MX}}_2$ are blue and green.

Explanation of Solution

For an ionic compound to have a formula of ${\text{MX}}_2$, the metal element must combine with the non-metal element in a $1:2$ ratio. The charge on the non-metal must be half the charge on the metal element in order to have a $1:2$ ratio between them.

The blue and the green boxes represent the elements barium and chlorine respectively. Barium and chlorine ionize to form ${\text{Ba}}^{2+}$ and ${\text{Cl}}^{-}$ ions. The charge on the barium ion is $+2$ whereas the charge on the chloride ion is $-1$. In order to balance the charge on the barium ion, two chloride ions must combine with one barium ion in a $1:2$ ratio as follows:

${\text{Ba}}^{2+}+2{\text{Cl}}^{-}\to {\text{BaCl}}_2$

Conclusion

The coloured boxes that represent the elements that will form an ionic compound with the formula ${\text{MX}}_2$ are blue and green.

(k)

Interpretation Introduction

Interpretation:

The coloured box that represents an element that forms no compound is to be determined.

Concept introduction:

A periodic table is an arrangement of elements based on their atomic number, properties and electronic configuration. The table is arranged into groups and periods. The elements which are metallic in nature, occupy the large lower-left portion of the table. The non-metals occupy the small upper-right portion of the table. Metalloids like along the staircase line. Elements which appear in the same group have similar behaviour.

Answer to Problem 2.135P

The coloured box that represents an element that forms no compound is purple.

Explanation of Solution

The coloured box purple represents the element argon. Argon is a noble gas element. Noble gases have high stability due to their completely filled shells. Hence noble gases do not gain or lose electrons. Hence the coloured box that represents an element that forms no compound is purple.

Conclusion

The coloured box that represents an element that forms no compound is purple.

(l)

Interpretation Introduction

Interpretation:

The coloured boxes that represent a pair of elements whose compounds exhibit the law of multiple proportions are to be determined.

Concept introduction:

Law of multiple proportions states that, if two elements can combine to form more than one compound, the masses of one element that combines with a fixed mass of the other element are in the ratio of small whole numbers.

Answer to Problem 2.135P

The pairs of coloured boxes that represent elements whose compounds exhibit the law of multiple proportions are, black and red, red and green, black and green, brown and red and blue and red.

Explanation of Solution

The pair of black and red box represent the elements of carbon and oxygen. The two common compounds with multiple proportions formed by them are $\text{CO}$ and ${\text{CO}}_2$.

The pair of red and green box represents the elements of oxygen and chlorine. The common compounds of oxygen and chlorine, in which both the elements are in different proportions are, ${\text{Cl}}_2\text{O}$, ${\text{ClO}}_2$, ${\text{Cl}}_2{\text{O}}_6$, ${\text{Cl}}_2{\text{O}}_7$, ${\text{Cl}}_2{\text{O}}_8$ etc.

The pair of black and green box represent the elements of carbon and chlorine. The common compounds of carbon and chlorine in which both the elements are in different proportions are ${\text{CCl}}_2$, ${\text{CCl}}_4$ etc.

The pair of brown and red box represent the elements of sodium and oxygen respectively. The common compounds of sodium and oxygen in which both the elements are in different proportions are ${\text{Na}}_2\text{O}$, ${\text{Na}}_2{\text{O}}_2$, ${\text{NaO}}_2$ etc.

The pair of blue and red box represent the elements barium and oxygen respectively. The common compounds of barium and oxygen in which both the elements are in different proportions are $\text{BaO}$, ${\text{BaO}}_2$ etc.

Conclusion

The pairs of coloured boxes that represent elements whose compounds exhibit the law of multiple proportions are, black and red, red and green, black and green, brown and red and blue and red.