An atom of chlorine will gain an electron and form a negative ion. The ionic bond is the electrostatic force of attraction between a positively charged metal ion and a negatively charged non-metal ion. Metals form positive ions because they lose electrons to become stable. Magnesium Mg has the electron arrangement 2,8,2. To become stable it must lose its two outer electrons to obtain a full outer energy level. Atoms are neutral because they have equal numbers of protons and electrons however, when they lose two electrons they are no longer neutral.
They change into ions with a two positive charge. For example, chlorine anion will be called chloride whereas sulfur anion, sulfide.
Ions or atoms of opposite charges tend to be attracted towards each other. This is as opposed to the phenomenon wherein ions or atoms with the same charge tend to repel. In this case, this is called electrostatic repulsion. In ionic bond, an electrostatic attraction works between oppositely charged ions where anions are chemically attracted to cations. The electron that can be donated or accepted may be more than one as long as the octet configuration is achieved. Thus, it can be expected that the net charge of the resulting compound i.
Chemical bonds, such as ionic bonds , help form a chemical compound. A chemical compound is a substance comprised of more than one type of atoms. Thus, a substance that is made up of only one type of atom is not a compound but a chemical element. A chemical compound in which the bond that holds atoms or particles together is called an ionic compound. An example of an ionic compound is the sodium chloride , NaCl. An ionic compound will be made up of both positive and negative ions.
Therefore, the oppositely charges ions in an ionic compound combines and balancing each other out resulting in a net charge of zero 0. Conversely, an ionic compound that has hydroxide OH — or oxide O 2- is classified as a base. An ionic compound formed by acid-base reactions and without those ions is called a salt.
While covalent bond involves the sharing of electrons between atoms, an ionic bond involves the transferring of electrons from one to another in order to achieve the stable configuration. However, this reaction is highly favorable because of the electrostatic attraction between the particles.
At the ideal interatomic distance, attraction between these particles releases enough energy to facilitate the reaction. Most ionic compounds tend to dissociate in polar solvents because they are often polar. This phenomenon is due to the opposite charges on each ion. In this example, the sodium atom is donating its 1 valence electron to the chlorine atom.
This creates a sodium cation and a chlorine anion. Notice that the net charge of the resulting compound is 0. In this example, the magnesium atom is donating both of its valence electrons to chlorine atoms. Each chlorine atom can only accept 1 electron before it can achieve its noble gas configuration; therefore, 2 atoms of chlorine are required to accept the 2 electrons donated by the magnesium.
Notice that the net charge of the compound is 0. Covalent bonding is the sharing of electrons between atoms. This type of bonding occurs between two atoms of the same element or of elements close to each other in the periodic table.
This bonding occurs primarily between nonmetals; however, it can also be observed between nonmetals and metals. If atoms have similar electronegativities the same affinity for electrons , covalent bonds are most likely to occur. Because both atoms have the same affinity for electrons and neither has a tendency to donate them, they share electrons in order to achieve octet configuration and become more stable.
In addition, the ionization energy of the atom is too large and the electron affinity of the atom is too small for ionic bonding to occur.
For example: carbon does not form ionic bonds because it has 4 valence electrons, half of an octet. To form ionic bonds, Carbon molecules must either gain or lose 4 electrons.
This is highly unfavorable; therefore, carbon molecules share their 4 valence electrons through single, double, and triple bonds so that each atom can achieve noble gas configurations. Covalent bonds include interactions of the sigma and pi orbitals; therefore, covalent bonds lead to formation of single, double, triple, and quadruple bonds.
In this example, a phosphorous atom is sharing its three unpaired electrons with three chlorine atoms. In the end product, all four of these molecules have 8 valence electrons and satisfy the octet rule. Ionic and covalent bonds are the two extremes of bonding.
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