Chapter 7, Problem 8ALQ

Interpretation Introduction

Interpretation:

To describe why the transfer of electrons is the evidence of a chemical reaction.

Concept Introduction:

When a neutral element gain electrons, the negative charge increases on it and it convert into negative ion. This negative ion is always greater than neutral ion.

${\text{O}}^{2-}>{\text{O}}^{-}>\text{O}$

Similarly, when a neutral element loss electrons, the negative charge decreases on it and it convert into positive ion. This positive ion is always smaller than neutral ion.

$\text{N}\text{a}>\text{N}{\text{a}}^{+}$

The compounds which contain ionic bond, which is a type of bond which formed between positive metal ion or cation and negative, non-metal ions or anion.

The compounds which contain covalent bond are covalent compound or molecular compound. This covalent bond is a type of bond which formed between two non- metal atoms by sharing of electrons. It forms between two non-metals. After sharing electrons the elements have noble gas arrangement of electrons.

A balanced chemical equation is an equation that contains same number of atoms as well as of each element of reactants and products of reaction.

For example, the reaction between lead sulphide and oxygen is as follows:

$\begin{array}{l}2\text{P}\text{b}\text{S}+\text{ 3 }{\text{O}}_2\to 2\text{P}\text{b}\text{O}+2\text{S}{\text{O}}_2\\ \text{ Reactants Products}\end{array}$

The most common driving forces which create product in chemical reactions are as follows:

1. Formation of a solid.
2. Formation of water.
3. Transfer of electrons.
4. Formation of gas.