Rock salt or sodium chloride is acrystalline solid. It occurs naturally as white cubic crystals. The structure of NaCl is formed by repeating the unit cell. It has an organized structure and has a 1:1 ratio of Na:Cl.NaCl is a face centered cubic unit cell which has four cations and four anions
6 of (Na) as well as 6 of (Cl) in NaCl i.e. rock type salt structure