Chapter 8, Problem 34A

Interpretation Introduction

Interpretation :

A synthesis or combination reaction must be explained with example. Whether this reaction can also be classified as other type of reaction must be explained. An example of synthesis reaction must be given which is a combustion reaction. An example of synthesis reaction must be given which is also an oxidation-reduction reaction but not a combustion reaction.

Concept Introduction :

A synthesis reaction is the one in which two or more than two substances combine to give a single product.

Answer to Problem 34A

A synthesis or combination reaction is a type of chemical reaction in which combination of substances take place to produce a single product.

This reaction can also be classified as oxidation-reduction reaction and combustion reaction.

An example of synthesis reaction which is also a combustion reaction is water formation from hydrogen and oxygen.

An example of synthesis reaction which is also an oxidation-reduction reaction but not a combustion reaction is the formation of hydrogen chloride gas from hydrogen and oxygen.

Explanation of Solution

  ${\text{N}}_{\text{2}}{\text{(g)+3H}}_{\text{2}}\text{(g)}\to {\text{2NH}}_{\text{3}}\text{(g)}\text{.}$

This is a combination reaction.

  ${\text{2H}}_{\text{2}}{\text{(g)+O}}_{\text{2}}\text{(g)}\to {\text{H}}_2\text{O(g)}\text{.}$

This is a synthesis reaction as well as combustion reaction.

  ${\text{H}}_{\text{2}}{\text{(g)+Cl}}_{\text{2}}\text{(g)}\to \text{2HCl(g)}\text{.}$

This is a synthesis reaction which is also an oxidation-reduction reaction in which hydrogen is oxidized and chlorine is reduced. But this is not a combustion reaction.