What are Interhalogen Compounds?
Interhalogen compounds are molecules that contain atoms of two different elements from the halogen group. The most common example of an interhalogen compound is chlorine trifluoride (ClF 3 ), which contains atoms of chlorine and fluorine.
Structure of Interhalogen Compounds
Interhalogen compounds are molecules that contain two or more different types of halogens. The bonding between the atoms is very strong, and the molecules are very stable.
The structure of an interhalogen compound can be predicted using the VSEPR theory. The halogens have a very negative electron affinity, so they will form a V-shaped structure, with the negative electrons in the middle.
Types of Inter-halogen Compounds
There are three types of inter-halogen compounds: ionic, covalent, and polar covalent.
Ionic inter-halogen compounds are formed when two ions of different elements combine. The ions are held together by electrostatic forces. Ionic compounds are generally soluble in water.
Covalent inter-halogen compounds are formed when two atoms of different elements share a pair of electrons. The atoms are held together by covalent bonds. Covalent compounds are not very soluble in water.
Polar covalent inter-halogen compounds are formed when two atoms of different elements share a pair of electrons. The atoms are held together by covalent bonds. However, one of the atoms is more electronegative than the other. This causes the shared electrons to spend more time near the more electronegative atom. This results in a polar covalent bond. Polar covalent compounds are soluble in water.
Preparation of Interhalogen Compounds
The preparation of interhalogen compounds proceeds by the substitution of a halogen atom in a molecule with another halogen atom. The two halogen atoms will form a covalent bond, and the compound will be a polar molecule. The polarity of the molecule will result in a net positive or negative charge on the atoms, which will determine the stability of the compound. The most stable interhalogen compounds will have a net positive charge on the atoms, while the least stable compounds will have a net negative charge.
Properties of Interhalogen Compounds
The bond length between any two atoms in a molecule is affected by the strength of the forces between those atoms. The stronger the forces, the shorter the bond length. In general, the forces between atoms in a molecule increase as the atoms get closer to each other.
The interhalogen bond lengths are shorter than the bond lengths between atoms of the same type in a molecule of the element alone. This is because the forces between atoms in a molecule of the element alone are weaker than the forces between atoms in a molecule of the element with another atom of a different type.
Uses of Interhalogen Compounds
There are many uses for interhalogen compounds. Some of these include:
• In the production of refrigerants
• As a flame retardant in plastics
• In the production of pharmaceuticals
• In the production of pesticides