1. Mosquito repellent (M) is contained within a cylindrical matrix (D = 3 cm, L = 15 cm) that is wrapped in a layer of cloth (3 mm thick). The matrix is a mixture of various liquid components including the repellent, which has a mole fraction (XM) of 0.35. The repellent evaporates and diffuses radially through the cloth as a gas into the surrounding air. The pure state vapor pressure of the repellent is 170 Pa. Assume an average wind speed of 5 m and an ambient air temperature is 27 °C. The repellent has different diffusivities in air (DM,air 0.02 cm²) and in the cloth (DM,cloth = 0.006 cm²). S S = Mosquito Repellent (M) Cloth Layer L = 15 cm Cross-sectional view 3 mm Air Flow D = 3 cm a. b. Determine the mass transfer coefficient (kc). Hint: In the CGS unit system, your answer will be less than 1. What is the initial rate of mosquito repellent release into the air (WM)? Do not use the rectangular approximation.

1. Mosquito repellent (M) is contained within a cylindrical matrix (D = 3 cm, L = 15 cm) that is wrapped in a layer of cloth (3 mm thick). The matrix is a mixture of various liquid components including the repellent, which has a mole fraction (XM) of 0.35. The repellent evaporates and diffuses radially through the cloth as a gas into the surrounding air. The pure state vapor pressure of the repellent is 170 Pa. Assume an average wind speed of 5 m and an ambient air temperature is 27 °C. The repellent has different diffusivities in air (DM,air 0.02 cm²) and in the cloth (DM,cloth = 0.006 cm²). S S = Mosquito Repellent (M) Cloth Layer L = 15 cm Cross-sectional view 3 mm Air Flow D = 3 cm a. b. Determine the mass transfer coefficient (kc). Hint: In the CGS unit system, your answer will be less than 1. What is the initial rate of mosquito repellent release into the air (WM)? Do not use the rectangular approximation.