Ionic Bond Definition

Atoms combine with each other to form compounds with properties different from the atoms they contain. The attractive force between the atoms in a compound is a chemical bond.

A type of chemical bond is the ionic bond. This corresponds to a force of attraction between species (ions) with opposite charges. Positively charged ions are known as cations; negatively charged ions are anions. Whether an element is the source of the cation or anion in an ionic bond depends on several factors, for which the periodic table can serve as a guide.

A type of chemical bond is the ionic bond. This corresponds to a force of attraction between species (ions) with opposite charges. Positively charged ions are known as cations; negatively charged ions are anions. Whether an element is the source of the cation or anion in an ionic bond depends on several factors, for which the periodic table can serve as a guide.

The ionic bond is the type of bond in which electrons can be transferred from one atom to another, resulting in the formation of positive and negative ions. Electrostatic attractions between positive and negative ions hold compounds together. It is also known as the electrovalent bond and is a type of bond formed from the electrostatic attraction between ions of opposite charge in a chemical compound.

This type of bond is formed when the valence electrons that are located in an outermost position of an atom are permanently transferred to another atom. The atom that loses the electrons becomes a positively charged ion or cation, while the one that gets them becomes a negatively charged ion or anion.

Ionic bond define

By forming ionic compounds, the elements to the left of the periodic table generally lose electrons and form a cation that has the same electronic configuration as the closest noble gas. The loss of an electron from sodium, for example, produces Na +, which has the same electronic configuration as neon.
To subtract an electron from an atom, a large amount of energy must be added, called ionization energy. The ionization energy of sodium, for example, is 496 kJ / mol (119 kcal/mol).

The processes that absorb energy are said to be endothermic. Compared to other elements, sodium and group 1A elements have relatively low ionization energies. In general, the ionization energy increases over one row on the periodic table.

The elements to the right of the periodic table tend to gain electrons to achieve the electronic configuration of the next higher noble gas. By adding an electron to chlorine, for example, the Cl - anion is formed, which has the same full-layer electron configuration as argon noble gas.

When a chlorine atom captures an electron, energy is released. Energy-releasing reactions are described as exothermic, and the energy change for an exothermic process has a negative sign. The energy change for adding an electron to an atom is known as its electron affinity and is 349 kJ / mol (83.4 kcal/mol) for chlorine.

Transferring an electron from a sodium atom to a chlorine atom produces a sodium cation and a chlorine anion, both of which have a noble gas electronic configuration:

If only the ionization energy of sodium (496 kJ / mol) and the electronic affinity of chlorine (349 kJ / mol) are added, it would be concluded that the total process is endothermic by 147 kJ / mol.

The energy released by adding an electron to chlorine is insufficient to satisfy the energy required to remove an electron from sodium. This analysis, however, does not consider the attractive force between ions with opposite charges Na + and Cl -, which exceeds 500 kJ / mol and is more than enough for the entire process to be exothermic. The forces of attraction between particles with opposite charges are called electrostatic, or coulombic, attractions, and is the meaning of an ionic bond between two atoms.

Ionic bonds are very common in inorganic compounds, but rare in organic ones. Carbon's ionization energy is too great and the electron affinity too small for carbon to form an anion or cation.

Ionic bond characteristics

Some of the most notable characteristics of ionic bonds are the following:

Ionic bonds have the ability to stay solid when they are at room temperature.
Its structure is crystalline or transparent.
They have high melting and boiling points.
They are bonds that result from the interaction that occurs between the metals of groups I and II and the nonmetals of groups VI and VII.
They are quite strong and depend entirely on ions.
They have a solubility in water and in some other aqueous solutions. This happens because they have an electric dipole that can break up ions.
They are excellent conductors of electricity when they are in an aqueous solution.
When they are in the solid-state they are not capable of conducting any kind of electricity.
Classification
Ionic bonds are classified depending on the ions that their compounds possess. In this way, there are anions and cations.

Ionic Bond Examples

Magnesium oxide (MgO)

Copper sulfate (CuSO4)

Potassium iodide (KI)

Zinc hydroxide (Zn (OH) 2)

Sodium chloride (NaCl)

Silver nitrate (AgNO3)

Lithium fluoride (LiF)

Magnesium chloride (MgCl2)

Potassium hydroxide (KOH)

Calcium nitrate (Ca (NO3) 2)

Calcium phosphate (Ca3 (PO4) 2)

Potassium dichromate (K2Cr2O7)

Disodium phosphate (Na2HPO4)

Iron sulfide (Fe2S3)

Potassium bromide (KBr)

Calcium carbonate (CaCO3)

Sodium hypochlorite (NaClO)

Potassium sulfate (K2SO4)

Manganese chloride (MnCl2)

How ionic bond is formed?

There are two main types of bonds: ionic and covalent. Ionic bonds are formed by the mutual attraction of particles of opposite electrical charge; Those particles, formed when an electron jumps from one atom to another, are known as ions.

For many atoms, the simplest way to complete the outer energy level is to gain or lose one or two electrons. Formation of transition metal ions All monatomic anions have noble gas electronic configurations.

However, not all monatomic cations have a noble gas electronic configuration. For example, all transition elements except palladium have one or two electrons in their outer shell. The difference in the electron configuration between one atom of a transition element and the next, in one period of the periodic table, is in the penultimate outer layer.

Most of the elements in the first transition series form ions with a +2 charge. Let's see, for example, the formation of iron (II) oxide: The ionic or electrovalent bond is formed when one or more electrons are transferred from one atom to another. Thus, a positive and a negative ion originate, which unite due to an electrostatic attraction.

Due to the nature of this type of bond, the ions formed do not constitute a molecule of one or more negative or positive ions. Instead, each positive ion is surrounded by negative ions and vice versa.

Therefore the formula for an ionic compound, such as that of sodium chloride (NaCl), does not indicate that a sodium ion combines with a chloride ion, but it does indicate that the relationship between the sodium ion and the chloride ion is one Na + for a Cl -.

Therefore, when speaking of ionic compounds, the term formula unit is normally used and the relative mass of this must be expressed as formula weight. However, the term molecular weight is often used for any type of compound.

How positive and negative ions are arranged in an ionic compound depends primarily on the size and charge of the ion. The electrostatic attraction between individual ions is rather a weak interaction.

However in the crystal structure formed, each ion is surrounded by several ions of opposite charge. This makes the bonding strength in ionic compounds very strong. Ionic compounds have relatively high melting points and boiling points due to this strong interaction.

The formula of an ionic compound simply depends on the charge of the ions that form it. For example, the sodium ion has a charge + 1 and the chloride ion - 1, so the formula for sodium chloride is NaCl. In the case of calcium chloride, since the calcium ion has a charge + 2 the formula is CaCl 2 .
Removing an electron from a sodium atom and forming a sodium ion gives the sodium atom great stability by acquiring the electronic configuration of the neon noble gas, which has eight electrons in its outer shell.

If an electron is added to a chlorine atom to produce a chloride ion, this atom takes on the external electronic configuration of the noble gas argon, which has eight electrons in its outer shell and is quite stable.

Remember that the two 4 s electrons separate before the 3 d electrons , because by removing them first you get a lower energy ion. For the Fe +2 , the electronic configuration [Ar] 3d 6 has less energy than the [Ar] 4s 2 3d 4 . The iron (II) ion, Fe +2 , does not have the noble gas electronic configuration.

Because each successive ionization energy is greater, it would require much more energy than is available under ordinary conditions to remove the eight external electrons from the iron atom.

However, there is not much difference in energy between the 3 d orbitals and the 4 s orbital . In the presence of oxygen, the iron (II) ion will react quickly to form the iron (III) ion. The third electron must be separated from the 3 d sublayer , because in the fourth layer there are no more electrons left:

The formation of more than one type of cation is a characteristic property of transition metals, because the s orbital of the outer layer ( n ) and the d orbitals of the penultimate outer layer ( n-1 ) have similar properties.

What is the difference between Ionic Bond and Covalent Bond?

Ionic Bond vs Covalent Bond

	Ionic bond	Covalent bond
What is it?	Also called an electrovalent bond. It is the union of a metal and a non-metal element.	It is the union of two non-metal elements.
Explanation	Metals lose an electron while nonmetals gain them (this completes the electronic octet).	The elements share electrons to form stable
	From this exchange, both elements result in opposite charges, which makes them attractive.	molecules (using the electronic byte).
		No exchange is done as in the ionic bond.
Union	Of a metal and a non-metal element. For example; chlorine + sodium = sodium chloride	Two nonmetal elements are joined. For
		example;
		chlorine + hydrogen = methane chloride
Outcome	Ionic networks form.	Instead, the result of covalent bonds are
		molecules.

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What is Ionic bond? Definition, Examples and formed