Chemical Engineering

A type 1-1 shell-tube condenser condenses 5000 kg/h of saturated ethanol vapor at normal pressure with cooling water at 25°C. Liquid ethanol exits the apparatus at a temperature of 600°C. The water leaving the device has a temperature of 400C. Let the heat coefficient of steam side is 6000W/m2.K, liquid ethanol side is 3000W/m2K, water side is 2000W/m2K. Let’s: a) Draw device diagram, line symbol b) Calculate the heat transfer coefficient of the device. c) Calculate the amount of water needed to cool down d) Calculate the number of pipes 21x2mm if L= 50 is selected.

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Two blocks of mass m1 = 2.00 kg and m2 = 6.00 kg on a frictionless table are connected by a massless string. Forces of magnitude F1 = 10.0N and F2 = 5.00N are applied as shown. The string remains taught during the motion. (a) Draw a free body diagram for each block. (b) Draw a free body diagram for the blocks and string treated as one system. (c) What is the acceleration of the blocks? (d) What is the tension in the string?(e) What are the normal forces exerted by the table on each block? (f) What is the net force (direction and magnitude) acting on m2

EXPERT ANSWER Normal force on m2 = m2g = 6*9.8 = 58.8 NNetforce on m2, F = F2 + T = 5 + 6.25 = 11.25 N in thr + ve X axis direction

It is necessary to grow a 1um field oxide to isolate the transistors in a certain bipolar technology. Due to concerns with dopant diffusion and stacking fault formation, the oxidation must be carried out at 1050 C. If the process is carried out in a wet ambient at atm. Pressure, calculate the required oxidation time. Assume that the parabolic rate coefficient is proportional to the oxidation pressure. Calculate the oxidation time required at 5 and at 20 atm.

It is necessary to grow a 1um field oxide to isolate the transistors in a certain bipolar technology. Due to concerns with dopant diffusion and stacking fault formation, the oxidation must be carried out at 1050 C. If the process is carried out in a wet ambient at atm. Pressure, calculate the required oxidation time. …

It is necessary to grow a 1um field oxide to isolate the transistors in a certain bipolar technology. Due to concerns with dopant diffusion and stacking fault formation, the oxidation must be carried out at 1050 C. If the process is carried out in a wet ambient at atm. Pressure, calculate the required oxidation time. Assume that the parabolic rate coefficient is proportional to the oxidation pressure. Calculate the oxidation time required at 5 and at 20 atm. Read More »

1.3 A concrete wall, which has a surface area of 20 m² and is 0.30 m thick, separates conditioned room air from ambient air. The temperature of the inner surface of the wall is maintained at 25°C, and the thermal conductiv- ity of the concrete is 1 W/m·K. (a) Determine the heat loss through the wall for outer surface temperatures ranging from -15°C to 38°C, which correspond to winter and summer extremes, respectively. Display your results graphically. (b) On your graph, also plot the heat loss as a function of the outer surface temperature for wall materials hav- ing thermal conductivities of 0.75 and 1.25 W/m•K. Explain the family of curves you have obtained.

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Design an ontology based on the following sentences: – Accidents can be categorised as chemical, electrical, fire, kinetic or liquid. – An accident can only be one of the above types. – An investigation is conducted for accidents. – An investigation only covers one accident.

EXPERT ANSWER Solution :- The ontology can be designed as follows: Accidents-hasType-hasInvestigation Chemical-isA Electrical-isA Fire-isA Kinetic-isA Liquid-isA Investigation-covers In Protege, this can be represented as follows: Accidents-hasType-hasInvestigation Chemical-isA Electrical-isA Fire-isA Kinetic-isA Liquid-isA Investigation-covers Explanation: The ontology is designed such that accidents have a type and an investigation. The types of accidents include chemical, electrical, fire, …

Design an ontology based on the following sentences: – Accidents can be categorised as chemical, electrical, fire, kinetic or liquid. – An accident can only be one of the above types. – An investigation is conducted for accidents. – An investigation only covers one accident. Read More »

Find the value of the isothermal compressibility of carbon dioxide gas at 298.15 K and a molar volume of 24.4 Lmol−1, a. According to the ideal gas law. b. According to the truncated virial equation of state:

Find the value of the isothermal compressibility of carbon dioxide gas at 298.15 K and a molar volume of 24.4 Lmol−1, a. According to the ideal gas law. b. According to the truncated virial equation of state: PVm/RT= 1+ B2/VmFor carbon dioxide at 298.15 K, B2 = −12.5 × 10−5 m3/mol. EXPERT ANSWER

Ventilating air enters a fan through a duct 1.6 m2 in area. The inlet static pressure is 2.54 cm of water less than atmospheric pressure. The air leaves the fan through a duct 0.87 m2 in area and the discharge static pressure is 7.68 cm water above atmospheric pressure. If the specific weight of the air is 1.2 kg/m3, and the fan delivers 9.5m3/s of air, determine: a.The power input on the air; b.The total dynamic head in water c.The fan efficiency if the power input to the fan is 12.5 Kw.

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