Which allotropic form of sulfur has a higher melting point: rhombic sulfur or monoclinic sulfur?
Rhombic sulfur has a higher melting point.
Monoclinic sulfur has a higher melting point.
Both forms have the same melting point.
Neither form has a melting point.
Option B Monoclinic sulfur has a higher melting point: This is the correct answer. Monoclinic sulfur has a melting point of 119.0°C, which is higher than the melting point of rhombic sulfur.
Explanation of incorrect option
incorrect option A Rhombic sulfur has a higher melting point: This is incorrect. Rhombic sulfur has a melting point of , which is lower than the melting point of monoclinic sulfur.
incorrect option C Both forms have the same melting point: This is incorrect. Rhombic sulfur and monoclinic sulfur have different crystal structures, which lead to differences in their physical properties, including their melting points.
incorrect option D Neither form has a melting point: This is incorrect. Both rhombic sulfur and monoclinic sulfur have melting points, which are well-established physical properties of these two allotropic forms of sulfur.