A. Air at 10°C and 1 atm flows over a plane surface covered with naphthalene. The flow velocity is such that the Reynolds number at a distance of 0.6 m from the leading edge of the plate is 9 ¥ 104. Determine the average mass transfer coefficient for the transfer of napthelene over the 0.6 m length of the surface by making use of the analogy between heat and mass transfer in laminar flow along a flat plate.
B. Air at 25°C and atmospheric pressure flows with a velocity of 7.6 m/s inside a 2.5 cm inner diameter pipe. The inside sur face of the tube contains a deposit of naphthalene. Determine the mass transfer coefficient for the transfer of naphthalene from the pipe surface into the air in regions away from the inlet.
