Temperature (°C) 1000 800 600 400 (a) Liquid + α (b) Liquid α+Y (c) 5 10 15 20 25 30 Composition (% Sn) →→→ Y Figure 2 Figure 2 shows a part of Copper(Cu)-Stanum(Sn) phase diagram. Based on this phase diagram answer the following questions. i. Identify phases (a) to (e). ii Identify two isothermal reactions. Write the equation for each reaction including the composition and temperature. Consider an alloy containing 20t % Sn: iii. 1. If the alloy is heated, at what temperatures the melting process begin and complete ? 2. What are the phases or phases exist and their compositions at the temperature of 850°C, 700°C and 400°C. 3. Determine the mass proportion of the phases present 700°C. 4. Explain with the aid of sketches the solidification process for this alloy when it is slowly cooled from the liquid phase to 700 °C.