Discuss the following problem:
Q: A spherical droplet of alcohol, 0.5 mm in diameter, is falling freely through quiescent air at a velocity of 1.8 m/s. The concentration of alcohol vapor at the surface of the droplet is 0.0573 kg/m3, and the diffusion coefficient for alcohol in air is 10-5 m2/s. Neglecting radiation and assuming steady-state conditions, calculate the surface temperature of the droplet if the ambient air temperature is 300 K. The latent heat of vaporization is 8.42 x 105 J/kg.