Analytical Chemistry Interview Questions
Questions Answers Views Company eMail

In my analysis by HPLC,In sample main peak and placebo peak are eluting with shorter resolution ( almost look like doublet). how can i get max resolution ? Is changing gradient method is usefull?

3 8743

what is the need of calulation of RRF of impurity in HPLC analysis?

9 22238

why SGF media used for dissolution . What is the use of it .can we use other media of lower pH instead ot this?

1 6246




what is difference between UV - VISIBLE MODEL NO like 1600,1601,1700 etc ? plz explain me

Graviti Pharmaceuticals,

1296

How do we get end points and how many end points are possible for citric acid and di-acid not theorotically answer should be given practically.

Reddy Labs, Hetero,

1283

only one end point is possible for citric acid and we get 2 end points for di acid why?

Reddy Labs,

3 5481

why kf factor coming 0.5

Alkem Labs,

5 12138

For Recent draft guidelines for Dissolution test apparatus calibration, why removing the salicylate tables?

Alkem Labs,

3 6755




How can v calibrate ftir ? Plz explain me

Cipla,

2 14888

what is the diff betwen calibration and system suitability?

8 13917

Why Methanol used in KF Titration?

Lupin, Glenmark,

15 50387

Why do we use 500ppb sucrose and 500ppb 1,4 benzoquinone in TOC calibration?

Vardhman,

2 6014

why chiral separation?

1 6130

what is main use of primary standards in caliration

Lupin, Nectar Lifesciences, Lee Pharma,

2 3254

what are the important specifications for a Column ?

2 7274


Post New Analytical Chemistry Questions






Un-Answered Questions { Analytical Chemistry }

HI,I CLEARED BOB CLERK EXAM. MY INTERVIEW WILL BE ON 9TH OCTOBER,2010.PLEASE SEND ME INTERVIEW QUESTIONS AND ANSWERS. THANK YOU.

1087


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.

967


My question about gas chromatography sulfur chemiluminsecence detector. I test unknown sample gas by GC-SCD (calibrated ) and the result of *H2S is 279 PPM , *but when I test the same sample with the GC-TCD (calibrated ) the value of *H2S is 2500 PPM . I'd like to inform you that both GCs are calibrated and have very good operation conditions with stable parameters . the question is if the sample gas with higher H2S over detection limits of SCD detector (1000 ppm). why the result it 279 ppm Best regards

293


how to calculate corelation coefficient in G.C Calibration? what is the calculation part?

1081


Tell me something about Vitamin A test method by HPLC

1441






How can the GC or HPLC method is selected to determine the impurity profile in drug product?

5565


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

332


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?

412


What is control room temperature and which guide line says?

440


some product having water content method with pyridine and ethylene glycol mixture instead of methanol? how they are selecting and methanol is not suitable solvent how ?

1238


Colorimtry

305


how can I make the copper get white bye any salt or acit?

1061


How do we get end points and how many end points are possible for citric acid and di-acid not theorotically answer should be given practically.

1283


how much mass should be there in volumetric flask while in preparation of sample for assay? 

1282


How will u perform degradation study in detectors other thann PDA in HPLC Methodology

1320