When two or more oppositely charged ions are held together due to the presence of electrostatic force, the resulting bond formed is termed an ionic bond. Simply, a chemical bond will be formed among two atoms by transferring one or more electrons from one atom to another.

In a reaction between metals and non-metals, metals generally lose electrons (form cations) to complete their octet, while non-metals gain electrons (form anions) to complete their octet. Metals and non-metals generally react to form ionic compounds.

Due to the presence of oppositely charged ions, ionic compounds are held strongly by the electrostatic force of attraction. Prominent properties of ionic compounds are:

• Physical Appearance: There is a strong force of attraction between positive and negative ions, which makes ionic compounds solid and not easily breakable.
• Melting and Boiling Points: Ionic compounds have a significant force of attraction between them. So, it requires a large amount of energy to break the ionic bonds between the atoms. That’s why ionic compounds have a higher melting and boiling point.
• Solubility: Ionic compounds can dissolve in polar solvents. Water, methanol, and formamide are some examples of polar solvents. Also, ionic compounds are insoluble or barely soluble in non-polar solvents like chloroform, hydrocarbons, etc.
• Electric Conductivity: Ionic compounds don’t conduct electricity in solid states, but they do conduct in the molten state. As you know, the conduction of electricity involves a transfer of charge from one point to another.
• In solid-state, the movement of ions is not possible, and thus, ionic compounds can’t conduct electricity. However, ionic compounds in the molten state can conduct electricity because their electrostatic forces of attraction get overcome by the heat released.
• They are brittle in nature.

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