Question

How would you compare the three types of bonds based on what happens to the valence electrons of the atoms?

Answer 1

Hint:The type of bonds formed between atoms to form molecules depends on the fact that whether the valence electrons is shared between the atoms, or the valence electrons are gained or lost in the reaction taking place.

Complete step-by-step answer:So in the question, it is asked that we should compare the three types of bonds on the basis of changes occurring with valence electrons.
From the lower classes we are studying about what is a chemical bond, how it is formed between the atoms etc. So let us briefly discuss chemical bonds, different types of bonds and how they are prepared.
A chemical bond consists of a pair of electrons between the atoms combined. In bonding the electrons involved are the valence electrons, the electrons in the outermost shell. Chemical bonds formed between the atoms during a chemical reaction are either by sharing the electrons or by loss or gain of electrons. There are three types of chemical bonds:
(a) Covalent bond
(b) Ionic bond
(c) Metallic bond
When the valence electrons are shared between the atoms and form the chemical bond. Such bonds are called covalent bonds. These types are formed between the atoms which will have less electronegativity difference between them.
In an atom, it loses an electron and forms a positively charged ion called cations and the electron is accepted by another atom which forms negatively charged species called anions. And the cations and anions combine to form the ionic bond. Such type of bonding is observed between a metal and a non-metal which has greater value for electronegativity difference.
Metallic bond is a type of chemical bond which is formed by the electrostatic attraction between the delocalized electrons and charged metal ions. Here the electrons are shared with the positive charged structure of the metal.

Note:If a bond is formed by the contribution of a pair of electrons completely from an atom Then that type of bond is called a co-ordinate bond. Co-ordinate bond is a dative bond which is also called a dative covalent bond or dipolar bond.