The typical BOD test of a municipal wastewater is 230 ppm at 20 °C. The amount of organic matter remaining in the sample after five days is equivalent to 180 mgO2/L. Calculate the BOD21 of the sample at 25 °C.

Q: [Evaporation] A triple effect evaporator concentrates a 10% caustic soda solution from 10% to 50%…

A: Introduction  Chemical engineers refer to a multiple-effect evaporator as a device for effectively…

Q: An aqueous solution contains 12 % Na2CO3 by weight. Express the composition in mole ratio and mole%.

A: let total mass of aqueous solution=100 g mass of Na2CO3=12 g moles of Na2CO3=mass of Na2CO3molecular…

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A: Aerosol has air content so the time expression has gas constant. The water density, viscosity, and…

Q: . A distilling column is fed with a solution containing 0.45mass fraction of benzene and 0,55 mass…

A: Given  Feed contain 0.45 mass fraction benzene and 0.55 mass fraction toluene

Q: A vegetable after drying to moisture content of 5% dry basis (weight basis) is to be packaged…

A: Given data: Initial moisture content of vegetable = 5 % dy basis Final moisture content of vegetable…

Q: Silica gel is to be used to separate a mixture of butane and butylene. The feed containing 55%…

A: Given :Feed at the bottom contains-Basis feed= 100 mol (supposed)Butane= 55% = 55 molButylene= 45%…

Q: Alum is used as a coagulant. The best dry alum dose from the jar tests is 10 mg/L. Assume dry alum…

A: Given that, The dose of alum = 10 mg/L Converting into kg/L, the dose is = 10 mg = 10×10-6 kg = 1×…

Q: Design of Absorption Tower A mixture of gas containing 90.5% mole % Hydrogen peroxide (H₂O2) and…

A: It is given that,the fraction of methanol recovered is mole fraction of methanol in the gas mixture…

Q: An evaporator is fed with 17400 kg/h of a solution containing 12.1% NaCl, 19.9% NaOH, and the rest…

A:

Q: Ethyl alcohol is diffusing into an alcohol-water solution at 18°C. The concentration of alcohol in…

A: The given question is a question of diffusion mass transfer.

Q: TASK 2: Q1 (a) Design of Absorption Tower A mixture of gas containing 80.9 mole % Hydrogen peroxide…

A: It is given that,the fraction of methanol recovered is mole fraction of methanol in the gas mixture…

Q: 80% RH, specific volume 16.5 Cu-ft of air / lb of dry air. Calculate what is wet bulb temperature,…

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Q: Exercise 3. Find the distance between the trays of a settling chamber to remove dust from a gas…

A: To calculate the distance between the trays of a settling chamber to remove dust from a gas stream,…

Q: Q1/ Aluminum is diffused into pure silicon to make a semiconductor material. How long should be the…

A: There are two question.Only first one is answered. Given data: Temperature=1300°C=(1300+273)K=1573K…

Q: In a textile mill, a double-effect evaporator system concentrates weak liquor containing 4 % solids…

A: Given that, Mass% of solids in the feed xF = 4% = 0.04 Mass% of solids in the product xP = 25% =…

Q: 4. Calculate the change in pH that results from adding 25 ml of 0.010F HCI to 500ml buffer solution…

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Q: Benzoic acid is very useful in the personal care industry to prevent infection caused by bacteria. A…

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Q: Silica gel is to be used to separate a mixture of butane and butylene. The feed containing 55%…

A: The feed is a mixture of butane and butylene with 55% and 45% by mole respectively. Silica gel is…

Q: 60% NaOH is to be concentrated in a triple effect evaporator to 15% NaOH. If equal amount of water…

A: The tripple effect evaporator system has been shown in figure The feed rate is F=100 kg/hr (Taking…

Q: Steel surface can be hardened by carburization. Such process is done at 1000°C and the concentration…

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Q: A 100 mol liquid mixture contains 50 % Benzene, 30 % Toluene and 20 % Xylene on a mole basis. On…

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Q: A uniform patch of clay soil initially has a moisture content of 96.6 g/kg dry soil. After a sudden…

A: Given data Initial moisture content = 96.6 g/kg dry soil, Saturated moisture content = 190.1 g/kg…

Q: 60% NaOH is to be concentrated in a triple effect evaporator to 15% NaOH. If equal amount of water…

A: Given  60%NaOH is concentrated in a triple effect evaporator to 15 %NaOH And equal amount of water…

Q: A multiple effect evaporator has a capacity to process 500 kg of solid caustic soda per day, when it…

A: Given that  500 kg of solid caustic soda per day c1  =3 %C2  = 28 %

Q: Silica gel is to be used to separate a mixture of butane and butylene. The feed containing 55%…

A: Feed at the bottom contains-Basis feed= 100 mol (supposed)Butane= 55% = 55 molButylene= 45% =45 mol

Q: Ethyl alcohol is diffusing into an alcohol-water solution at 18°C. The concentration of alcohol in…

A: The given question is based on diffusion mass transfer and application of film theory.

Q: Silica gel is to be used to separate a mixture of butane and butylene. The feed containing 55%…

A:

Q: Ethyl alcohol is diffusing into an alcohol-water solution at 18°C. The concentration of alcohol in…

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Q: 68%NaOH is to be concentrated in a triple effect evaporator to 16% NaOH.If equal amount of water is…

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Q: How long will it take to deposit 1.5 g of Cu on a metal when a current of 5A is applied to a CuSO4…

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Q: 10,000 kg of a 20% solution of sodium nitrate is concentrated to saturation. Crystals of sodium…

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Q: A low-density polyethylene membrane of 0.1 um in thickness is used for separating oxygen from air.…

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Q: 2) Determine the minimum mass of ethylene glycol (C2H6O2) that must be dissolved in 14500 g water to…

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Q: An aqueous solution containing 60% Na2S2O3 and 1% soluble impurities is diluted with water and fed…

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Q: Exercise 3. Find the distance between the trays of a settling chamber to remove dust from a gas…

A: To calculate the distance between the trays of a settling chamber to remove dust from a gas stream,…

Q: ,The internal energy change in the conversion of 1.0 mole of the calcite form of CACO3 to the…

A: