A sphere of naphthalene of 6cm diameter is sublimated in air moving at 5m/s (convective problem). Our final goal is to calculate the half-life time of this sphere (the time it takes for the sphere to have a diameter of 3cm ). Additional information: Air is at 113F and 1atm. The molecular weight and density of naphthalene is 128g/mol and 71.1lb/ft3, respectively. The vapor pressure of naphthalene at this condition is 0.8 mmHg. Diffusion of naphthalene in air at 45C is 6.92106m2/s, density and viscosity of air are 1.1 kg/m3 and 1.92105kg/(ms). Assume a stagnant layer of 1mm around this sphere. 1. Calculate Reynolds, Smith and Sherwood numbers at the initial time (diameter is 6cm ). What is the value of kc at these conditions? 2. Calculate Reynolds, Smith and Sherwood numbers at when the diameter is 3cm. What is the value of kc at these conditions? Use the following Sherwood relationship: Sh=2+0.6Re0.5Sc0.33with2Re800and0.6Sc3200