Ionic bonds happen when one atom gains one or more electrons from another atom. The electrons in an atom have a negative charge and are equal in number to the positively charged protons in the nucleus. When an atom gains or loses electrons, the balance of charges is broken, so the atom becomes either positively or negatively charged. It is called an ion. An atom that has gained electrons has a negative charge and is called an anion. One that has lost electrons has a positive charge and is called a cation. As opposite charges attract each other, the two atoms that have gained and lost electrons are pulled together into a bond.
When two atoms combine, they form a compound or molecule in a chemical bond, which links them together. This bond can be ionic or covalent. In an ionic bond, one atom donates an electron to the other to stabilize it. In a covalent bond, the atoms are shared by the electrons.
In the chemistry world, an ionic bond is made from atoms with different electronegativity values. It is considered a polar bond if the attraction is between two oppositely charged ions. This works much in the same way as magnets that attract each other. If two atoms have different electronegativity values, they will make an ionic bond.
The combination of sodium (Na) and chloride (Cl) forms NaCl or common table salt, and this is an example of an ionic bond. Sulfuric acid is also an ionic bond, combining hydrogen and sulfur oxide, and it is written as H2SO4.
Ionic bonds take more energy to break than covalent bonds, so ionic bonds are stronger. The amount of energy needed to break a bond is known as bond dissociation energy, which is basically the force it takes to break bonds of any type.
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