For the separation of which of the following substances, Gas-solid chromatography is being used Select one: a. Low molecular weight gaseous species O b. Volatile organic components O c. Thermally stable organic components Clear my choice Next page Which of the following(s) is / are true? The peak fronting occurs when some site of solute molecules retained more strongly than others, - The peak tailing occurs when the amount of solute introduced onto column is too large. m- The efficiency of the column increases as the plate height becomes smaller Select one: al and it b. Only cil and in d. Il and 111 e. None of them f. Only Ol, ll and in h Only 11 Clear my choice Sample injection port must be maintained at a temperature at which rapid vapourisation occurs but thermal degradation does not occur. Select one: True False Which of the following(s) is / are correct? 1- Guard column is used to prevent impurities and increase the lifetime of analytical column Il- In normal phase chromatography, hydrophilic substances are eluted firstly through the column. III- lon-exchange chromatography allows the separation of ionisable molecules on the basis of differences in polarities Select one: O a. Only 11 O b. Only 1 O c. I and 11 d. Il and I O'e. None of them f. Only III 9. l, ll and in h. I and II HPLC method does not involves Select one: O a. lon chromatography O b. adsorption chromatography c. Partition chromatography . d. Paper chromatography O e. Affinity chromatography Clear my choice