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Water in the bottom of a narrow metal tube is held at a constant temperature of 25°C.The total pressure of air (assumed dry) is 1.013 x 105 Pa (1.0 atm) and the temperatures 25°C. Water evaporates and diffuses through the air in the tube, and the diffusion path z2z₁ is 0.0762 m (0.25 ft) long. i. Calculate the rate of evaporation at steady state conditions in mol/s-m². The diffusivity of water vapour at 298 K and 1 atm pressure is 0.25 x10-4 m²/s.Assume that the system is isothermal. ii. If the available surface area for water evaporation is 5 m² and the rate of evaporation is equal to the previous result how many kg of water will be evaporated per day under these conditions? Is this analysis realistic? The vapor pressure of water at 25°C is 23.76 mmHg.

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