The solid states of rock salt (NaCl), ice (H2O), and diamonds (C) have distinct structures due to the differences in the arrangement of their constituent atoms or molecules.
Rock Salt (NaCl): Rock salt, also known as sodium chloride, has a crystalline structure and belongs to the cubic crystal system. In its solid state, the sodium (Na+) and chloride (Cl-) ions are arranged in a repeating pattern called a face-centered cubic lattice. Each sodium ion is surrounded by six chloride ions, and vice versa. This structure gives rise to the characteristic cubic shape of salt crystals.
Ice (H2O): Ice is the solid state of water, and its structure is based on the arrangement of water molecules. Ice exhibits a hexagonal crystal structure and belongs to the hexagonal crystal system. In this structure, water molecules (H2O) form a network of interconnected hexagonal rings. Each water molecule is bonded to four neighboring water molecules through hydrogen bonds. The arrangement of these hydrogen bonds results in the formation of a lattice-like structure in which the water molecules are held in a fixed position.
Diamonds (C): Diamond is a crystalline form of carbon. Its solid-state structure is a three-dimensional network of carbon atoms arranged in a crystal lattice. Each carbon atom in a diamond is covalently bonded to four neighboring carbon atoms in a tetrahedral arrangement. This interconnected network of carbon atoms gives diamonds their exceptional hardness and unique optical properties.
In summary, the differences in the structures of rock salt, ice, and diamonds arise from variations in the arrangement of atoms or molecules within their respective crystal lattices. These variations in structure contribute to the distinct properties exhibited by these solid states.