Chapter 24, Problem 88QP

Interpretation Introduction

Interpretation:

The similar behavior of chlorine, bromine, and iodine is to be explained.

Concept introduction:

The elements of the same group exhibit similar chemical properties due to the presence of the same number of valence electrons.

All the halogens are the most reactive and toxic in nature.

The tendency of reactivity decreases down the group. Thus, fluorine is the most reactive element among all the halogens.

The elements bromine, chlorine, and iodine belong to group 17 and are known as halogens.

All the halogens combine with hydrogen to form the hydrogen halide.

The sodium salt of the halogens reacts with silver nitrate to form the silver salts.

All the halogens are good oxidizing agents as they have the tendency to oxidize the other substance and reduce themselves in the chemical reactions.

The oxidizing power of the halogens decreases down the group. Among chlorine, bromine, and iodine, chlorine act as the strongest oxidizing agent, followed by bromine and iodine.

All the halogens combine with sodium hydroxide salt to form the corresponding halide, hypo halite, and water molecule.

Answer to Problem 88QP

Solution:

Bromine, chlorine, and iodine react with hydrogen to form corresponding hydrogen halide.

The sodium salt of halogens reacts with silver nitrate to form the silver salts.

Bromine, chlorine, and iodine oxidize the elemental phosphorus to their corresponding halide, thus acting as strong oxidizing agents.

Bromine, chlorine, and iodine react with sodium hydroxide to form the corresponding halide and hypo halite.

The chemical properties of fluorine different from the other halogens are described below.

Explanation of Solution

a)With hydrogen

In the periodic table, the elements of the same group tend to show almost similar chemical properties due to the presence of the same number of valence electrons. The elements bromine, chlorine, and iodine belong to group 17 and are known as halogens.

All the halogens combine with hydrogen to form the hydrogen halide. The similar behavior of the given elements with hydrogen is shown by the chemical reactions.

The reaction of chlorine with hydrogen to form hydrogen chloride is as follows:

${\text{Cl}}_2(g)+{\text{H}}_2(g)\to 2\text{HCl}\left(g\right)$

The reaction of bromine with hydrogen to form hydrogen bromide is as follows:

${\text{Br}}_2(g)+{\text{H}}_2(g)\to 2\text{HBr}\left(g\right)$

The reaction of iodine with hydrogen to form hydrogen iodide is as follows:

${\text{I}}_2(g)+{\text{H}}_2(g)\to 2\text{HI}\left(g\right)$

Hence, the similar behavior of chlorine, bromine, and iodine with hydrogen is explained.

b) In producing silver salts

In the periodic table, the elements of the same group tend to show almost similar chemical properties due to the presence of the same number of valence electrons. The elements bromine, chlorine, and iodine belong to group 17 and are known as halogens.

The sodium salt of the halogens reacts with silver nitrate to form the silversalts. The similar behavior of the given elements for the preparation of silver salts is shown by the chemical reactions.

The reaction of sodium chloride with silver nitrate to form silver chloride is as:

${\text{AgNO}}_3(aq)+\text{NaCl}(aq)\to 2\text{AgCl}\left(s\right)+{\text{NaNO}}_3\left(aq\right)$

The reaction of sodium bromidewith silver nitrate to form silver bromide is as:

${\text{AgNO}}_3(aq)+\text{NaBr}(aq)\to 2\text{AgBr}\left(s\right)+{\text{NaNO}}_3\left(aq\right)$

The reaction of sodium iodide with silver nitrate to form silver iodide is as:

${\text{AgNO}}_3(aq)+\text{NaI}(aq)\to 2\text{AgI}\left(s\right)+{\text{NaNO}}_3\left(aq\right)$

Hence, the similar behavior of chlorine, bromine, and iodine for the formation of silver salt is explained.

c) As oxidizing agents

In the periodic table, the elements of the same group tend to show almost similar chemical properties due to the presence of the same number of valence electrons. The elements bromine, chlorine, and iodine belong to group 17 and are known as halogens.

All the halogens are good oxidizing agents as they have the tendency to oxidize the other substance and reduce themselvesin the chemical reactions. The oxidizing power of the halogens decreases down the group. Thus, among chlorine, bromine, and iodine, chlorine act as the strongest oxidizing agent, followed by bromine and iodine.

The oxidizing power of the given elements is shown by the chemical reactions in which the elemental phosphorus is oxidized.

Chlorine is used to oxidize the phosphorus into phosphorus chloride. Thus, the reaction of chlorine reacting with phosphorus to form phosphorus chloride is as:

${\text{P}}_4+6{\text{Cl}}_2\to 4{\text{PCl}}_3$

Bromine is used to oxidize the phosphorus into phosphorus bromide. Thus, the reaction of bromine reacting with phosphorus to form phosphorus bromide is as:

${\text{P}}_4+6{\text{Br}}_2\to 4{\text{PBr}}_{\text{3}}$

Iodine is used to oxidize the phosphorus into phosphorus iodide. Thus, the reaction of iodine reacting with phosphorus to form phosphorus iodide is as:

${\text{P}}_4+6{\text{I}}_2\to 4{\text{PI}}_{\text{3}}$

Hence, the oxidizing agent tendency of chlorine, bromine, and iodine is explained

d) With sodium hydroxide

In the periodic table, the elements of the same group tend to show similar chemical properties due to the presence of the same number of valence electrons. The elements bromine, chlorine, and iodine belong to group 17 and are known as halogens.

All the halogens combine with sodium hydroxide salt to form the corresponding halide, hypo halite, and water molecule. The similar behavior of the given elements with hydrogen is shown by the chemical reactions.

The reaction of chlorine with sodium hydroxide to form sodium chloride and sodium hypochlorite is as:

${\text{Cl}}_2+2\text{NaOH}(aq)\to \text{NaCl}\left(aq\right)+\text{NaOCl}\left(aq\right)+{\text{H}}_2\text{O}\left(l\right)$

The reaction of bromine with sodium hydroxide to form sodium bromide and sodium hypobromite is as:

${\text{Br}}_2+2\text{NaOH}(aq)\to \text{NaBr}\left(aq\right)+\text{NaOBr}\left(aq\right)+{\text{H}}_2\text{O}\left(l\right)$

The reaction of iodine with sodium hydroxide to form sodium iodide and sodium hypoiodide is as:

${\text{I}}_2+2\text{NaOH}(aq)\to \text{NaI}\left(aq\right)+\text{NaOI}\left(aq\right)+{\text{H}}_2\text{O}\left(l\right)$

Hence, the similar behavior of chlorine, bromine, and iodine with sodium hydroxide is explained.

e)Fluorine is not a typical halogen element

The elements fluorine, bromine, chlorine, and iodine belong to group 17 and are known as halogens.

Fluorine is not considered as a typical halogen because itshows chemical properties that are different from the other halogens. This is due to its small size and high electronegativity. The different properties of fluorine are as follows:

The silver salt of fluorine is soluble in water while the silver salts of all the other halogens are insoluble in water.

The hydrofluoric acid produced by fluorine is considered as a weak acid while the acid produced by the other halogens is considered asa strong acid.

Fluorine reacts with sodium hydroxide to form oxygen difluoride and sodium fluoride while the corresponding halide and hypo halite are obtained as products from the reaction of the halogens with sodium hydroxide.