Table of Contents
1. What is chemical combination?
2. Electrovalent (ionic) bonds
6. Differences between ionic (electrovalent) and covalent bonds
What is chemical combination?
Chemical combination is the process by which two or more elements or substances react chemically to form a new substance called a compound. During chemical combination, the atoms of the reacting substances are rearranged through the breaking and formation of chemical bonds. The resulting compound has properties that are usually different from those of the substances that formed it. For example, hydrogen and oxygen are gases under ordinary conditions. However, when they combine chemically in the correct proportion, they form water, which is a liquid under ordinary conditions.
The chemical equation is:
2H2 + O2 → 2H2O
Continue reading: What Is Chemical Combination? Meaning, Types, and Examples
Electrovalent (ionic) bonds
Ionic bonding is a type of chemical bonding that occurs when one or more electrons are transferred from one atom to another, resulting in the formation of positively and negatively charged ions that are held together by strong electrostatic forces of attraction.It is also known as electrovalent bonding. The atom that loses electrons becomes a positively charged ion called a cation, while the atom that gains electrons becomes a negatively charged ion called an anion.The attraction between these oppositely charged ions produces an ionic bond. this type of bond is common between metals and non-metals.
Continue reading: Electrovalent (Ionic) Bonding: Meaning, Formation, Properties and Examples
Covalent bonds
Covalent bonding is a type of chemical bonding in which two atoms share one or more pairs of electrons to achieve a more stable electronic arrangement. The shared electrons are attracted to the nuclei of both atoms, holding the atoms together. Covalent bonds commonly form between non-metal atoms. Examples include hydrogen, oxygen, nitrogen, chlorine and carbon.For example, when two hydrogen atoms combine to form a hydrogen molecule (H2), each hydrogen atom contributes one electron to a shared pair. Each hydrogen atom then has access to two electrons in its outer shell, giving it a stable duplet arrangement.
H + H → H2
Continue reading: Covalent Bonding: Meaning, Types, Formation, Properties and Examples
Dative covalent bonds
A dative covalent bond is a type of covalent bond in which both electrons forming the shared pair are donated by one atom, while the other atom provides an empty orbital to accommodate the electron pair. It is also known as a coordinate bond or coordinate covalent bond.
In this type of bonding, the atom that supplies the electron pair is called the donor, while the atom that accepts the electron pair is called the acceptor.
Continue reading:Covalent Bonding: Meaning, Types, Formation, Properties and Examples
Metallic bonds
Metallic bonding is the electrostatic force of attraction between positively charged metal ions arranged in a lattice and a sea of delocalised electrons moving throughout the structure. In a metallic structure, the outermost electrons of metal atoms become delocalised. This means that they are not restricted to individual atoms or particular bonds. As a result, the metal atoms become positive ions arranged in a regular structure, while the delocalised electrons move throughout the entire metallic lattice.
Continue reading: Metallic Bonding: Meaning, Formation, Properties and Examples
Differences between ionic (electrovalent) and covalent bonds
The type of chemical bonding present in a substance influences its physical properties.
However, it is important to remember that covalent substances include both simple molecular substances and giant covalent structures. Their properties can therefore vary considerably.
A. Melting and Boiling Points
Ionic compounds:
Most ionic compounds have high melting and boiling points because strong electrostatic attractions hold their oppositely charged ions together in a crystal lattice. A large amount of energy is needed to overcome these attractions. For example, sodium chloride has a melting point of approximately 801°C.
Simple molecular covalent substances:
Many simple molecular substances have relatively low melting and boiling points because the forces between their molecules are weaker than the ionic attractions in an ionic crystal. Examples include methane and oxygen.
Continue reading: Differences Between Ionic and Covalent Bonding: Formation, Properties and Examples
.png)
0 Comments