Why metal is a good THERMAL conductor but plastic is a worse conductor than metal? Is it also due to the delocalised electrons of the metal?plz explain it.
ya!its due to the delocalised electrons,plz bear in mind that,do not write free electrons during exams,or marks will be deducted!u must write DELOCALIZED ELECTRONS.
giant metallic structure---delocalized electrons
giant ionic structure-----mobile ions
giant covalent-----delocalized
simple molecular struct.----absence of mobile ions
Yes, the difference in thermal conductivity between metal and plastic is indeed due to the presence of delocalized electrons in metals. To understand this concept, let's break it down step by step:
1. Atomic Structure: Metals and plastics have different structures at the atomic level. Metals have a lattice structure, where atoms are arranged in a repeating pattern, forming a closely packed network. On the other hand, plastics have a more amorphous structure, with long chains of molecules that are not as tightly packed.
2. Bonding: The type of bonding within the material also affects thermal conductivity. In metals, the bonding is primarily metallic bonding, where electrons are shared by multiple atoms, forming a "sea" of delocalized electrons. This delocalization allows for easy transfer of thermal energy. In contrast, plastics have primarily covalent bonding, where electrons are shared between specific pairs of atoms. This type of bonding restricts the movement of electrons and hinders thermal energy transfer.
3. Delocalized Electrons: The presence of delocalized electrons in metals is a crucial factor in their high thermal conductivity. When heat is applied to a metal, the delocalized electrons can move freely throughout the lattice structure, carrying thermal energy rapidly. This process is called electron conduction. Additionally, metals usually have a higher density of electrons available for conduction compared to plastics, further enhancing their thermal conductivity.
4. Restricted Electron Movement in Plastics: In plastics, the covalent bonds between atoms restrict the movement of electrons, preventing efficient thermal energy transfer. The long chains of molecules in plastics do not provide a pathway for thermal conduction as metals do with their lattice structure and delocalized electrons. As a result, plastics are comparatively poor thermal conductors.
In summary, the high thermal conductivity of metals is due to their lattice structure, which allows for the presence of delocalized electrons that can easily transfer heat throughout the material. On the other hand, plastics have a more amorphous structure and covalent bonding, which restrict the movement of electrons and hinder thermal conductivity.