posted by Nancy on .
Can someone check to see if my answers look ok.
For the following crystals, explain how their melting points are related to the bonding forces and the crystal structure:
Copper has metallic bonds between atoms. It can occur as isometric cubic and octahedral crystals, but this is rare. The melting point is 1084.62 °C. The metalic bonds are strong, but the crystals are small and the thermal conductivity is high.
Water as a solid has covalent molecular bonds between atoms and hydrogen bonding between molecules. It has hexagonal crystals. The melting point is 0 °C. Hydrogen bonds are weak so not much energy is required.
Sodium chloride has ionic bonding in cubic close packed (ccp) crystals. The melting point is 801 °C. The temperature for melting must break ionic bonds and electrostatic forces.
Diamond is tetrahedrally covalent bonded carbon atoms in a face centered cubic lattice. It has a melting point of 3547 °C. The covalent bonds are very strong.