Final answer:
The identity of the unknown powder depends on its properties; if it shows characteristics of ionic compounds, it is KCl, but if it has properties of covalent compounds, it is C10H8.
Step-by-step explanation:
To determine whether an unknown powder is KCl (potassium chloride) or C10H8 (napthalene), we can look at their bonding and properties. KCl is known to form ionic bonds because it is composed of a metal (potassium) and a nonmetal (chlorine), as indicated in several examples where compounds with similar compositions are predicted to be ionic. On the other hand, C10H8 is composed of carbon and hydrogen, which are nonmetals, leading to the formation of covalent bonds.
Since ionic compounds are formed by metals and nonmetals, and covalent compounds are formed by nonmetals, the properties of the unknown powder will reveal its identity. If the data shows properties of ionic compounds (such as high melting and boiling points, solubility in water, and electrical conductivity when dissolved), the powder is KCl. Conversely, if the data shows properties of covalent compounds (such as lower melting and boiling points, poor solubility in water, and lack of electrical conductivity), then the powder is C10H8.