Answer Posted / raees sayyed

You probably mean referencing the chemical shift scale (?) For NMR spectra you don't report absolute absorption frequencies but you reference them with respect to an internal standard. For 1H NMR spectra this internal standard is usually tetramethylsilane (TMS). You add a very small amount (ca. 0.03 per cent) of TMS to the solution to be measured (or you buy a solvent that already contains TMS) and report the peak positions of your compound relative to the TMS signal. I. e. TMS is the zero point of your chemical shift scale.

on saturation solubility study data how we can find out the bcs class of drug?

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what is third integration

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EXPLAIN THE CALCULATION PART OF AN KF TITRATOR CALIBRATION WITH SUITABLE EXAMPLE

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what you do when compound having dwel wavelength?

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if you have given one product then how you determine the impurity in that?

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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.

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Many times I don't got a caffeine peak in calibration of hplc using guard column ❓

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what is the principle involved in turbidometry and nephelometry ?

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What is aggregate and fragments in SEC?

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how to calibrate hplc & gc

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What is the main difference between ODS1 and ODS2 Hplc column.

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what is impurity profile. how to interpret this impurity profile to a drug product or drug substance.

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why we are using hexane in calibration of number of drop per mL

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WHAT IS THE PARAMETER FOR THE SELECTION OF MOBILE PHASE IN HPLC?

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is it necessary to do HPLC calibration at wavelength 315nm if we are doing analysis at this wavelangth

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