Answer Posted / abdul razaque

primary standards are those substances having constant concentration ( they do not react with moist)
secondary standard are those substances whose variable concentration ( they react with moist)

in which situation ion pair agent require to use?

675

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

2146

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how decide the clining method and cleaning method validation require for this perticular products?

705

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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

1546

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

1921

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For limit test of heavy metals in BP, Method C require that the substance is ignited at a temperature not exceeding 800 °C. Why confines such the temperature?

4002

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How to start the dissolution development for unknown tab?

1613

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for which product require to do content uniformity? what is limit of cu?

743

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How to determine water content of bis tetrazole amine mono ammonium salt

3423

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what is the importance of peak purity in HPLC and how we can calculate through manul(not software)?

4419

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how you determine moist.of NaOH sol or NaOH flacks

2173

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in which situation require to change rs specification?

702

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what is mean by peak intigrity?

862

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Why sodium hydroxide used for maintain pH of phosphate buffer

2330

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identification is for unknown? qualification for known? reporting for LOQ?

664

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