Identify the following compounds as ionic or covalent:
MgO
C2H5OH
HCl
LiCl
The correct answer and explanation is :
Identification of Compounds as Ionic or Covalent:
- MgO (Magnesium Oxide) – Ionic
Magnesium oxide is an ionic compound because it is formed by the transfer of electrons between magnesium (Mg) and oxygen (O). Magnesium, a metal, loses two electrons to become ( Mg^{2+} ), while oxygen, a non-metal, gains two electrons to become ( O^{2-} ). The oppositely charged ions attract each other to form the ionic bond. - C2H5OH (Ethanol) – Covalent
Ethanol is a covalent compound because it consists of non-metals (carbon, hydrogen, and oxygen) that share electrons to form bonds. In ethanol, the carbon atoms are bonded to hydrogen atoms and the oxygen atom is bonded to the hydrogen atom. Since there is no complete electron transfer between atoms, the bonds are covalent. - HCl (Hydrochloric Acid) – Covalent
Hydrochloric acid is a covalent compound. It consists of hydrogen and chlorine, both of which are non-metals. The chlorine atom shares an electron with the hydrogen atom, forming a covalent bond. This sharing of electrons rather than an exchange indicates a covalent bond. - LiCl (Lithium Chloride) – Ionic
Lithium chloride is an ionic compound. Lithium, a metal, loses one electron to form ( Li^{+} ), while chlorine, a non-metal, gains the electron to form ( Cl^{-} ). The oppositely charged ions are held together by electrostatic forces, creating an ionic bond.
Explanation:
The classification of compounds as ionic or covalent depends on the type of atoms involved and the nature of the bond between them.
- Ionic compounds are formed when there is a significant difference in electronegativity between the two atoms involved, usually a metal and a non-metal. The metal loses electrons to become a positively charged ion (cation), and the non-metal gains electrons to become a negatively charged ion (anion). The attraction between the oppositely charged ions forms an ionic bond. Example: MgO and LiCl.
- Covalent compounds are formed when two non-metals share electrons to achieve a stable electron configuration. This sharing of electrons does not result in the formation of ions. Example: C2H5OH and HCl.
Visual Representation:
Ionic and covalent bonds for these compounds.
Here is a visual representation of the two types of bonds:
- On the left side, you can see the ionic bond in magnesium oxide (MgO), where magnesium transfers electrons to oxygen, creating positive and negative ions that attract each other.
- On the right side, you can see covalent bonds in ethanol (C2H5OH) and hydrochloric acid (HCl), where atoms share electrons to form stable molecules.