Metals, non-metals and ions make a bond to stabilize them. For metals, there is metallic bonding. For non metals, there is covalent bonding. Do you know about the bonding of ions? In this lesson we will be learning about ionic bonding.
What is Ionic Bonding?
Ionic bonding occurs between a cation (metal) and an anion (non-metal). Cation is when metals lose their electrons to stabilize them, for example sodium loses its 1 electron and becomes a cation (Na+). When a nonmetal gains electrons to stable them, anions are formed for example chlorine gains one electron and becomes (Cl-). Cations and Anions both have charges according to their losing and gaining of electrons. If they lose 2 electrons the charge would be 2+ as the ion has 2 more protons than electrons. When an atom gains 2 electrons, it becomes negatively charged (2-) as it has 2 more electrons than protons.
Ionic bonding is the electrostatic force of attraction between positive and negative ions. For example, Na+ makes a bond with Cl- to make NaCl. Sodium transfers one of its electrons to Chlorine.
Sodium atom loses its outer electron to become an ion.
The second one is chlorine atom which gains an electron to become chlorine ion (Cl-) Basically, in ionic bonding electrons are transferred to attain the stability of a noble gas (2 or 8 electrons in the outermost shell). Na+ Cl-, opposite signs cancel out each other and the formula derived is NaCl.
Let's have a look at other examples.
Magnesium oxide is also formed by ionic bonding. Magnesium transfers its 2 electrons to oxygen so its Mg2+ and O2- both the signs and the same charge cancel out each other and the formula is MgO.
If we talk about lithium oxide ( where lithium is a metal and oxygen is a non-metal ). In this reaction 2 atoms of lithium transfers its 2 electrons to oxygen and attains the charge of +1 on each atom, whereas 1 atom of oxygen attains the charge of -2. Li charge of + is cancelled out by O charge of -. The 2 on oxygen will transfer to lithium according to the chemical formula making rule. Hence, the compound formed has the formulae, Li O
2
To conclude with, metals always give their valence electrons (either 1,2 or 3) to the non metals (which already have either 5,6 or 7 valence electrons).
*All pictures are taken from google*
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