UNIT OPERATION - EXAMPLE 9.2 : A distillation column separates 10000 kg / hr of a mixture containing equal mass of benzene and toluene. The product D recovered from the condenser at the top of the column contains 95 % benzene, and the bottom W from the column contains 96 % toluene. The vapor V entering the condenser from the top of the column is 8000 kg / hr. A portion of the product from the condenser is returned to the column as reflux R, and the rest is withdrawn as the final product D. Assume that V, R, and D are identical in composition since V is condensed completely. Find the ratio of the amount refluxed R to the product withdrawn D. Hint : Solve the simultaneous equations as follow in order to find the answer (R / D) : 10000 = D + W; 10000 (0.5) = D (0.95) + W (0.04); 8000 = R + D.

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X is a solid having a white colour at room temperature. It has a density about 2g/cc. Although it has melting point near 325 degree Celsius, its properties start degrading above 260 degree Celsius. The coefficient of friction is very low about 0.1. It has very good dielectric properties especially at higher radio frequencies. It has a very high bulk resistivity. It is chemically inert. It is also resistant to van der Waals force. It is hydrophobic as well as lipophobic. Creep or ‘Cold Flow’ has been observed in X.

0 Answers   Ford,

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Explain what types of metals are typically removed via chemical precipitation?

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What are the disadvantages of using gear pumps?

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Given, T1=600C, constant temperature of wall 800 , length of wit exchanger L=3m, dia=25 mm, Cp=14.91 KJ/kg.K, density ρ=914 kg/m3,mean velocity vm= 2 m/s, film heat transfer coefficient hf=72 Kcal/h.m2.K, what is the outlet temperature?

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Do you have any idea on recombinant protein expression?

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how much time will take 20000 liter water to cool from 80-30 0C ? Assume all parameters constant

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ENGINEERING PHYSICS - EXAMPLE 30.4 : (a) Time evolution in Heisenberg picture, according to Ehrenfest theorem is m (d / dt) < r > = < p >, where m = mass, r = position, p = momentum of a particle. If v = velocity, prove that m < v > = < p >. (b) Lande g-factor is given by Gj = Gl [ J (J + 1) - S (S + 1) + L (L + 1) ] / [ 2J (J + 1) ] + Gs [ J (J + 1) + S (S + 1) - L (L + 1) ] / [ 2J (J + 1) ]. If Gl = 1 and under approximation of Gs = 2, prove by calculation that Gj = (3/2) + [ S (S + 1) - L (L + 1) ] / [ 2J (J + 1) ].

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why rotameter has variable area?? is it necessary??

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For an ideal black body (A) absorptivity = 1 (B) reflectivity = 1 (C) emissivity = 0 which is true???????

4 Answers   GATE, KFCL,

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Question 72 - (a) According to United States Department of Agriculture (USDA) (http://ndb.nal.usda.gov/ndb/search/list, accessed 12 August 2016), 100 g of potatoes generate 77 kcal of energy. For raw tomatoes, 111 g have 18 kcal of energy. Question : How much energy will one gain if 150 g of heated potatoes are eaten with 200 g of raw tomatoes? (b) If 1 Calorie = 1 food Calorie = 1 kilocalorie and 1000 calories = 1 food Calorie, then how many Calories are there in 9600 calories? (c) According to a food package of potato chips, 210 Calories are produced per serving size of 34 g. In actual experiment of food calorimetry lab, 1.75 g of potato chips, when burnt, will produce 9.6 Calories. For each serving size of potato chip, find the difference of Calories between the actual experimental value and the value stated on the food package. (d) The specific heat of water is c = 1 cal / (g.K) where cal is calory, g is gram and K is Kelvin. Then what is the temperature rise of water, in degree Celsius, when 150 g of water is heated by 9600 calories of burning food?

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How to size the cooling tower sump / basin for any given circulation rate? What is the guideline?

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