Which of the following types of bonding does not involve the formation of new substances?

1. Analyze the question

The question asks us to identify which type of chemical bonding does not result in the formation of a new chemical substance (a compound). In chemistry, bonding usually involves the interaction of atoms to achieve stability, often leading to the creation of new compounds with properties different from the constituent elements.

2. Explain the concept

• Covalent bonding: Involves the sharing of electrons between non-metal atoms to form molecules (new substances like $H_2O$ or $CO_2$).
• Co-ordinate (Dative) bonding: A type of covalent bond where both electrons in the shared pair come from the same atom. This also results in the formation of new chemical species (e.g., the ammonium ion, $NH_4^+$).
• Electrovalent (Ionic) bonding: Involves the complete transfer of electrons from a metal to a non-metal, resulting in the formation of ionic compounds (new substances like $NaCl$).
• Metallic bonding: This is the force of attraction between "free-moving" valence electrons (the "sea of electrons") and the positively charged metal ions in a metallic lattice. Metallic bonding occurs between atoms of the same metal element. It does not create a new chemical compound; it simply holds the atoms of the metal together in its solid state.

3. Show the solution

• When atoms of sodium ($Na$) bond with chlorine ($Cl$), they form sodium chloride ($NaCl$), which is a new substance with properties totally different from the reactive metal and the poisonous gas. This is electrovalent bonding.
• When hydrogen and oxygen atoms bond, they form water ($H_2O$), a new substance. This is covalent bonding.
• When copper atoms are bonded together in a piece of copper wire, they are held by metallic bonding. The copper remains copper; no new chemical substance is formed. The bonding is simply an internal force maintaining the structure of the element.

4. Identify the answer

Based on the analysis, metallic bonding is the only option listed that describes the interaction between atoms of the same element to maintain its structure, rather than a reaction creating a new chemical compound.

5. Tip

Think of Metallic bonding as a "community" of the same type of atoms holding hands, whereas Covalent, Co-ordinate, and Electrovalent bondings are "marriages" between different types of atoms that result in a "new family" (a new compound).