To determine which statement is true regarding the phase diagram, we must first understand what each arrow signifies in the context of phase changes.
Arrow A, representing melting, indicates the transition from solid to liquid. This occurs when a solid substance absorbs enough heat to break the bonds holding its molecules in a fixed position.
Arrow B, representing sublimation, refers to the transition from solid to gas without passing through the liquid phase. This process happens under specific conditions of pressure and temperature, as seen in substances like dry ice.
Arrow C, which denotes condensation, illustrates the transition from gas to liquid. When gas molecules lose energy, they come together to form a liquid.
Based on these definitions, the accuracy of statements about each arrow can be assessed. If the phase diagram clearly labels these transitions accordingly, then the answer would be that arrows A, B, and C accurately represent melting, sublimation, and condensation, respectively. If there’s inconsistency in the diagram or the directions of the arrows, then it might lean towards ‘none of the above.’ It’s essential to analyze the diagram carefully to draw the correct conclusion.