This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'The following phase diagram (in which Liquid + Beta solid solution -----------→ Alpha solid solution) shows: \nSelect and explain. \nA. Eutectic alloy, B. Peritectic alloy, C. Both, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The peritectic reaction is\xa0an invariant reaction that occurs at a particular composition and temperature. The reaction during the cooling process can\xa0be written as:\nLiquid +\xa0β solid solution\xa0→ α solid solution\xa0\nFigure\xa0is\xa0the\xa0phase\xa0diagram\xa0for\xa0the\xa0Ag-Pt alloy\xa0system.\xa0 The α\xa0phase is silver-rich,\xa0the β\xa0phase is platinum-rich, and the two-phase (α-plus-β) region results from the limited solid solubility of less than approximately 12% Ag in Pt at 700°C (point F) of silver in platinum. Figure shows that the equilibrium solid solubility of Pt in Ag is approximately 56% at 700°C. The peritectic transformation occurs at point P, where the liquid composition at B and the platinum-rich β\xa0phase\xa0 (composition at point\xa0D)\xa0transform into the silver-rich α phase (composition at point P).', 'role': 'assistant'}]