2. (17%) (a) (i) A beaker containing 400g of ice at -5C to is placed on a heater. How much heat is required to turn the beaker of ice to water at 15C? (Specific heat capacity of water = 4200Jkg-C-, specific latent heat of fusion of ice = 3.34105Jkg-, specific heat capacity of ice = 2108 Jkg-C-) (6) (ii) Suppose the heater takes 2 hours to finish the process in (a)(i). What is the power of the heater? (2) (b) Melting ice of mass 80g is added to 250g of liquid A at 50C. Find the final temperature of the mixture, assuming that no energy is lost to surroundings. (The specific heat capacity of water is 4200J kg- C-. The specific heat of fusion of ice is 3.34105Jkg-. The latent heat of fusion of solid A is 2400J kg-. The specific heat capacity of liquid A is 4500Jkg- C-. The melting point of A is -2C.) (6) (c) An insulated cylinder contains an ideal gas Y. The volume, temperature and pressure of gas Y is 125 cm, 30 C and 5x105Pa respectively. Find the number of molecules of gas Y in the cylinder if k=1.3810-2 J/K. (3)