Chapter 9, Problem 122A

(a)

Interpretation Introduction

Interpretation: Choose the more electronegative element from each of the given pairs.

Concept Introduction: The tendency of a covalently bonded atom to attract the bonded pair of electrons towards it is known as electronegativity. It is a unit less quantity.

Answer to Problem 122A

Lithium is more electronegative than cesium.

Explanation of Solution

The electronegativity of elements decreases on moving down the group in a periodic table. So when we compare the second element and sixth element of a group, the second element lithium has a higher electronegativity than cesium, the sixth element.

(b)

Interpretation Introduction

Interpretation: Choose the more electronegative element from each of the given pairs.

Concept Introduction: The tendency of a covalently bonded atom to attract the bonded pair of electrons towards it is known as electronegativity. It is a unit less quantity.

Answer to Problem 122A

Among strontium and iodine, iodine has the higher electronegativity value.

Explanation of Solution

Both strontium and iodine belong to the fifth period of the periodic table. But strontium is an s-block element lying on the left side and iodine is a p-block element lying on the right side. The electronegativity of elements increases on moving left to right across the period. Thus iodine is more electronegative than strontium.

(c)

Interpretation Introduction

Interpretation: Choose the more electronegative element from each of the given pairs.

Concept Introduction: The tendency of a covalently bonded atom to attract the bonded pair of electrons towards it is known as electronegativity. It is a unit less quantity.

Answer to Problem 122A

On comparing sulfur and magnesium, sulfur has higher electronegativity values than magnesium.

Explanation of Solution

Sulfur and magnesium belong to the third period. Magnesium is a second group element while sulfur is a Group 6A element. On moving from left to right electronegativity increases. Hence, S has a higher electronegativity than Mg.

(d)

Interpretation Introduction

Interpretation: Choose the more electronegative element from each of the given pairs.

Concept Introduction: The tendency of a covalently bonded atom to attract the bonded pair of electrons towards it is known as electronegativity. It is a unit less quantity.

Answer to Problem 122A

Among oxygen and selenium, oxygen has a higher electronegativity value.

Explanation of Solution

Oxygen and selenium belong to the same group with oxygen being the first member and selenium the third one. The electronegativity value decreases on moving down the group in a periodic table. So oxygen has a higher electronegativity than selenium.

(e)

Interpretation Introduction

Interpretation: Choose the more electronegative element from each of the given pairs.

Concept Introduction: The tendency of a covalently bonded atom to attract the bonded pair of electrons towards it is known as electronegativity. It is a unit less quantity.

Answer to Problem 122A

The electronegativity value of nitrogen is higher than that of tellurium.

Explanation of Solution

Nitrogen and tellurium belong to adjacent groups. Nitrogen in the precedent group should have lesser electronegativity than tellurium, but the latter belongs to the fifth period where the nuclear attraction is very weak when compared with those of nitrogen in the second period. So, nitrogen attracts electrons more effectively than tellurium and has a greater electronegativity than tellurium.

(f)

Interpretation Introduction

Interpretation: Choose the more electronegative element from each of the given pairs.

Concept Introduction: The tendency of a covalently bonded atom to attract the bonded pair of electrons towards it is known as electronegativity. It is a unit less quantity.

Answer to Problem 122A

Among carbon and fluorine, fluorine is more electronegative.

Explanation of Solution

Carbon belongs to Group 4A and fluorine belongs to Group 7A. Fluorine is two groups right to carbon in the periodic table and hence has a higher electronegativity than carbon.