Chapter 21, Problem 21QAP

Interpretation Introduction

(a)

Interpretation:

A balanced chemical equation for preparation of ${\text{F}}_{\text{2}}$ from HF needs to be determined.

Concept introduction:

The group-17 of the periodic table is also called as halogens. They are most reactive and most electronegative non-metals. The reactivity and electronegativity of elements decreases down in the group. The F atom is most electronegative in nature, it forms a weak acid with hydrogen.

Interpretation Introduction

(b)

Interpretation:

A balanced chemical equation for preparation of ${\text{Br}}_{\text{2}}$ from $\text{NaBr}$ needs to be determined.

Concept introduction:

The group-17 of the periodic table is also called as halogens. They are most reactive and most electronegative non-metals. The reactivity and electronegativity of elements decreases down in the group. In other words; in displacement reactions, a more reactive halogen can displace a less reactive halogen to form product. For example, chlorine can displace bromine from its solution but vice-versa is not possible. The reactivity order for halogens is:

$\text{F2 > Cl2 > Br2 > I2}$

Interpretation Introduction

(c)

Interpretation:

A balanced chemical equation for preparation of ${\text{NH}}_4^{+}$ from ${\text{NH}}_3$ needs to be determined.

Concept introduction:

Ammonia ${\text{NH}}_3$ can act as a base in aqueous solution this is due to the presence of lone pair of electrons on N atom.

A species can act as a base if it accepts hydrogen ion from the solution or donate hydroxide ion.