Question 94 - The resolution of separation, Rs for chromatography is given by th

Question 94 - 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.

Question Posted / kangchuentat

1 Answers
2874 Views
I also Faced
E-Mail Answers

Question 94 - The resolution of separation, Rs for chromatography is given by the formula Rs = (diff..

Answer / kangchuentat

Answer 94 - Reference formula Rs = (difference in retention time) / (average width at the base) is used. (a) First equation : Rs = (Tb - Ta) / [ (Wa + Wb) / 2 ] = 2 (Tb - Ta) / (Wa + Wb). Second equation : Rs = (Tc - Ta) / [ (Wa + Wc) / 2 ] = 2 (Tc - Ta) / (Wa + Wc). (b) Substitute Ta = Tc - Tb, Wa = 20 s, Wb = 40 s and Wc = 30 s into first equation and second equation. First equation : Rs = 2 = 2 [ Tb - (Tc - Tb) ] / (20 + 40) = (2 Tb - Tc) / 30, 2 Tb - Tc = 60. Second equation : Rs = 4 = 2 [ Tc - (Tc - Tb) ] / (20 + 30) = Tb / 25, Tb = 100 s. Substitute Tb = 100 s into first equation gives 2 Tb - Tc = 2 x 100 - Tc = 200 - Tc = 60, then Tc = 200 - 60 = 140 s. Then Ta = Tc - Tb = 140 - 100 = 40 s. 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.

Is This Answer Correct ?

0 Yes

0 No

Post New Answer

More Chemical Engineering Interview Questions

is the QURAN GOD'S words?

6 Answers

how to find a liquid flow's direction in a closed pipe by merely seeing it(without pressure gauges)...

4 Answers

ENGINEERING MECHANIC - EXAMPLE 15.3 : A biochemical trolley of mass 15 kg is towing a trailer of mass 5 kg along a straight horizontal pathway. The trailer and the trolley are connected by a light inextensible tow-bar. The engine of the trolley exerts a driving force of magnitude 100 N. The trailer and the trolley experience resistances of magnitude 10 N and 30 N respectively. (a) Form 2 equations with unknowns T and a, that represents the equilibrium for the 2 systems of the trolley and trailer. (b) Solve the simultaneous equations from the 2 equations that are obtained in part (a) of this question. T is the tension of the tow-bar and a is the acceleration.

1 Answers

Why LMTD is calculated in Heat -Exchanger problems..Why dont we take average temperature??

4 Answers Aker Solutions,

Corenuts technology interview questions

0 Answers

ENVIRONMENTAL ENGINEERING - QUESTION 22.3 : A well delivers 225 US-gallons per minute of water to a chemical plant during normal system operation. (a) Calculate its flowrate in the unit of mega US-gallon per day or MGD. (b) The following formula is written next to the chlorine feed point : (chlorine feed rate, lb / day) = (flowrate, MGD) X (dose, mg / L) x (8.34). If this formula is correct, then what should the chlorine feed rate to be in pounds per day (lb / day) if the desired dose is 2 mg / L. (c) Prove by calculations that the constant 8.34 in the formula next to the chlorine feed point is correct. Let 1 US-gallon = 3.78541 L and 1 mg = 0.0000022046 pound.

1 Answers

PROCESS DESIGN - EXAMPLE 21.1 : According to rules of thumb in chemical process design, consider the use of an expander for reducing the pressure of a gas when more than 20 horsepowers can be recovered. The theoretical adiabatic horsepower (THp) for expanding a gas could be estimated from the equation : THp = Q [ Ti / (8130a) ] [ 1 - (Po / Pi) ^ a ] where 3 ^ 3 is 3 power 3 or 27, Q is volumetric flowrate in standard cubic feet per minute, Ti is inlet temperature in degree Rankine, a = (k - 1) / k where k = Cp / Cv, Po and Pi are reference and systemic pressures respectively. (a) Assume Cp / Cv = 1.4, Po = 14.7 psia, (temperature in degree Rankine) = [ (temperature in degree Celsius) + 273.15 ] (9 / 5), nitrogen gas at Pi = 90 psia and 25 degree Celsius flowing at Q = 230 standard cubic feet per minute is to be vented to the atmosphere. According to rules of thumb, should an expander or a valve be used? (b) Find the outlet temperature To by using the equation To = Ti (Po / Pi) ^ a.

1 Answers

What are the different ways in which solids can be blended?

0 Answers

how much maximum power can be generated by 320v, 10kg-cm synchronus motor if shaft is roteted mechanically at 50 to 60 rpm?

0 Answers

Explain about different types of lamps?

0 Answers

hai please please if any one have useful test related and interview based question plz send me at saify_0@hotmail.com i will be thankfull

0 Answers

What are angle of repose applications in the chemical industry?

0 Answers

For more Chemical Engineering Interview Questions Click Here