Analytical Chemistry Interview Questions
Questions Answers Views Company eMail

Why we use caffeine for HPLC calibration in Detector wave ength accuracy test

Reddy Labs, Aurobindo, Cipla, Arvind, Shasun Chemicals,

59 139891

Why we use holmium oxide,perchloric acid for uv/vis calibration

Cipla, Ratiopharm, Orchid,

4 19509

Why Deuterium lamp is used as UV light Source for UV.

4 12653

What is principle of Polarimeter?


21 62819

What is unit of KF?


7 31880

what is principle of XRD?


3 21336

What is unit of pH?

26 34117

How to calibrate glassware against std calibrated glassware?

Cadila, Hetero,

3 9384

One pH means how much volts and milivolts?

Dr Reddys,

7 21680

Why sodium lamp is used as source of Polarimeter?

NCL, Zydus Cadila, College School Exams Tests, Hetero,

12 42472

why there is a need of optical activity & specific optical activity measurement by polarimeter


6 8583

What is normality


12 15828

what is principal of karl ficher instrument!

Alkem Labs, USV,

12 27333

How many clauses in ISO!

1 8927

Why 10%,20%,30% Sucrose solution is used for the calibration of polarimeter?

Cipla, LGC Promochem,

5 18778

Post New Analytical Chemistry Questions

Un-Answered Questions { Analytical Chemistry }

2. Two grams of Benzoic acid are dissolved in 200 ml of water and extracted with 200 ml of diethyl ether. The distribution coefficient of benzoic acid is 100, and its dissociation constant is 6.5 10-5. Calculate the distribution ratio (D) of benzoic acid at pH 2, 5, and 6. 3. Calculate D at pH 2 to 10 (1 unit apart) in the above problem, and plot D versus pH.


mode of absorption in alimentary canal?


how to selecet an exact coloumn for an new molecule development by hplc how to select exact salt as buffer for new molecule development by hplc what is the the process to select the mode of saparation of compoundes by hplc what is the use of ph of buffer what is use of buffer,ph,organic phase,ans methods how the molecules get saparated in coloumn,


I have compare C2H2-air and C2H2-N2O flame AAS on determination calcium. Both use same range of std to plot calibration curve. (2-6ppm) When i measure the sample with phosphate, KCl and LaCl, C2H2-N2O flame give false positive result, around 0.5ppm. When i measure the sample with phosphste, KCl and EDTA. C2H2-N2O flame also give 0.5ppm false positive. But both above mentioned sample would not give false positive when measured by C2H2-air flame. What is the reason?


How to check hplc detecter sensitivity?


Why do we use KMnO4 in the test of control of obsorbance ? and why do we take specific quantity i.e 57-63mg?


what is separation techniques.


What is stray light in uv what are units for stray light


In IR spectra, generally a molecule vibrates without apply emr or ir light?


How do we quantify crystaline and amarpous forms by using (NMR, XRD)spectroscopic techniques? Which any others instruments are useful for this quantification? explain


how will you do the prep for unstable componds?


For titration in anhydrous media with perchloric acide, if lack of titrator, Which indicator is been used for replacement. How calculate pH of test solution to choose suitable indicator?


Please tell me about the pH of Polycaboxylic ether is it in the 5-6 range ever or more than 6


In HPLC calibration, caffeine is used as primary standard for wave length calibration due to caffeine is having dual maxima at 273 & 205 nm and one minima at 245 nm. Any body can give reference of these details from any pharmacopeia (with chapter no.) or any other authentic guideline?


what is the difference between potentiometric titration and karl fischer titration?