Answer Posted / venkatesh

1.In the TOC Calibration Sucrose working as a test solution
and 1,4 benzoquinone working as a standard or Control
solution.

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?

1453

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what is difference in ods I ods II is this is realy from sorbent / packing characteristics or from other means

1485

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What is column in chromatography?

1759

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what is turbidimetric titration?Give 2 examples.

1986

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Why are use silicon oil mr?

743

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WHY pKa value is more important than pH value of the mobile phase in HPLC?

1255

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If combination product how require to identify which imp is of which api?

320

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What is the formula to determine the concentration of M of a solution given the % transmittance? Use %T = 43.7 as an example.

2116

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how to calculate elemental impurities?

542

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How to calculation of residual solvent methanol (3000 ppm) standard solution, and how many quantity used of test sample

2533

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how to set sample and standard concentration in RS method?

360

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what is definition of validation? which components are followed give detail?

1827

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What is control room temperature and which guide line says?

1156

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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

1111

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what is mean by dissolution hydrodynamics?

350

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