Answer / kang chuen tat (malaysia - pen

Answer 52 - (a) dC / dt = -kC, dC / C = -k dt. Integrate both sides gives ln C - ln Co = ln (C / Co) = -kt, C = Co exp (-kt). (b) When C / Co = 0.5, t = [ ln (C / Co) ] / (-k) = [ ln (0.5) ] / (-0.139) = 4.9867 minutes. (c) Step 1 : 16 to 8 mol per cubic metre. Step 2 : 8 to 4. Step 3 : 4 to 2. Step 4 : 2 to 1. Each step takes t minutes. There are 4 steps needed from 16 to 1 mol / cubic metre or 4t = 19.9468 minutes. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.

CHEMICAL FLUID MECHANIC - EXAMPLE 3.1 : Water flows through a pipe with circular cross sectional area at the rate of V / t = 80 L / s where V is the volume and t is time. Let Av = 80 L / s where A is cross sectional area and v is velocity of fluid. For point 1, the radius of the pipe is 16 cm. For point 2, the radius of the pipe is 8 cm. Find (a) the velocity at point 1; (b) the velocity at point 2; (c) the pressure at point 2 by using Bernoulli's equation where P + Rgy + 0.5 RV = constant. P is the pressure, R = density of fluid, V = square of fluid's velocity, g = gravitational constant of 9.81 N / kg and y = 2 m = difference of height at 2 points. The pressure of point 1 is 180 kPa.

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BIOCHEMICAL ENGINEERING INSTRUMENTATION - EXAMPLE 29.4 : The resolution of separation, Rs for chromatography is given by the formula Rs = (difference in retention time) / (average width at the base). In a chromatogram, 3 peaks a, b and c are found. Average widths W at the bases of the solutes are : Wa = 20 s, Wb = 40 s, Wc = 30 s. Resolutions of separation, Rs for solutes b and c in comparison to a are 2 and 4 respectively. The differences in retention times T for b and c in comparison to a are (Tb - Ta) and (Tc - Ta), Ta = Tc - Tb : (a) Form 2 equations involving Rs as a function of Wa, Wb, Wc, Ta, Tb and Tc. (b) Find the values of Ta, Tb and Tc.

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Why an electromagnetic flow meter cannot be used for gases, steam and oil flow measurements?

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Explain what are the problems that are associated with the expansion joints?

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Question 27 – By using Excel or other easiest programming package, explain how I, the integral of sin x dx from 0 to 3.142 could be approximated using random number. Find the exact value of I.

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Why should a magnesium ribbon be cleaned before burning in air?

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.1 : As an approximation, let v = Zc / 137 where v is the radial velocity for 1 s electron of an element, c is the speed of light, Z is the atomic number. For gold with Z = 79, find the radial velocity of its 1 s electron, in term of c and percentage of the speed of light. (b) As an approximation, let A x A = 1 - Z x Z / 18769 where A is the ratio of the relativistic and non-relativistic Bohr radius. Find the value of A.

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ENGINEERING MECHANIC - EXAMPLE 15.1 : What is the meaning – strain? In a distillation column, if a block 10 cm on a side is deformed so that it becomes 9 cm long, what is the strain involved in percentage?

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hello everyone do anyone have interview questions for any chemical industry please email me at ravijallu.nitj@gmail.com

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Suppose you have hot fluid and cold water, what fluid you should flow in shell side and tube side in a shell and tube heat exchanger and why

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Question 34 – In the distillation of binary systems by Mc Cabe Thiele method, the equation for the line of top section is given by y = [ R / (R + 1) ] x + XD / (R + 1). 2 points on the line are (0.99, 0.99) and (0, 0.36). Find the reflux ratio of R and XD.

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how does the properties of an element changes by increasing protons and electrons?

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