To determine which compound among the given options has the highest melting point, we need to consider their chemical bonding and structure.
A. KBr (Potassium Bromide)
- KBr is an ionic compound composed of potassium (K) and bromine (Br).
- Ionic bonds are generally very strong because they are the result of the electrostatic forces between oppositely charged ions.
- Ionic compounds typically have high melting points due to the strong attraction between the ions in the solid state.
B. PCl[tex]\(_5\)[/tex] (Phosphorus Pentachloride)
- PCl[tex]\(_5\)[/tex] is a covalent compound composed of phosphorus (P) and chlorine (Cl).
- Covalent bonds are usually weaker than ionic bonds.
- PCl[tex]\(_5\)[/tex] exists as a molecular solid in which the molecules are held together by relatively weak van der Waals forces, leading to a lower melting point compared to ionic compounds.
C. CCl[tex]\(_4\)[/tex] (Carbon Tetrachloride)
- CCl[tex]\(_4\)[/tex] is a covalent compound composed of carbon (C) and chlorine (Cl).
- Similar to PCl[tex]\(_5\)[/tex], it is held together by van der Waals forces.
- Molecular solids like CCl[tex]\(_4\)[/tex] typically have relatively low melting points due to the weak intermolecular forces.
D. SF[tex]\(_6\)[/tex] (Sulfur Hexafluoride)
- SF[tex]\(_6\)[/tex] is also a covalent compound composed of sulfur (S) and fluorine (F).
- This compound exists as a discrete molecular solid with weak van der Waals forces holding the individual molecules together.
- It has a low melting point typical of molecular compounds.
Given the characteristics of each compound, we can conclude that:
- Ionic bonding in KBr results in a significantly higher melting point compared to the covalently bonded molecular compounds PCl[tex]\(_5\)[/tex], CCl[tex]\(_4\)[/tex], and SF[tex]\(_6\)[/tex].
Therefore, among the options provided, the compound with the highest melting point is:
A. KBr (Potassium Bromide).
