Which structural feature explains graphite's conductivity?

Which structural feature explains graphite's conductivity?

• A. Layers of hexagonal rings with weak interlayer forces and delocalized electrons
• B. A three-dimensional covalent network with no free electrons
• C. Metallic bonding throughout the structure
• D. An ionic lattice with mobile ions

Answer: (A)

Graphite conducts electricity because its structure includes layers of hexagonal rings where electrons are delocalized within each layer. In each plane, carbon atoms form strong in-plane sigma bonds with three neighbors, and the remaining p electrons create a delocalized pi-system that can move freely along the layer. This roaming electron cloud carries charge, giving good conductivity within the planes. The layers are held together by weak interlayer forces, so while conduction happens mainly in the planes, the structure isn’t a metallic solid with electrons free in all directions. The other descriptions don’t fit graphite: a fully covalent 3D network without free electrons would be an insulator, metallic bonding implies a true metal with electrons across the whole lattice, and an ionic lattice requires mobile ions, not a carbon framework.

Graphite conducts electricity because its structure includes layers of hexagonal rings where electrons are delocalized within each layer. In each plane, carbon atoms form strong in-plane sigma bonds with three neighbors, and the remaining p electrons create a delocalized pi-system that can move freely along the layer. This roaming electron cloud carries charge, giving good conductivity within the planes. The layers are held together by weak interlayer forces, so while conduction happens mainly in the planes, the structure isn’t a metallic solid with electrons free in all directions. The other descriptions don’t fit graphite: a fully covalent 3D network without free electrons would be an insulator, metallic bonding implies a true metal with electrons across the whole lattice, and an ionic lattice requires mobile ions, not a carbon framework.