Chem2 Labs  WS/96
Gas Chromatography
Postlab


1.   If I inject 0.50 ml of pure CHCl3 vapor into a GC at 25.0 oC and 1.00 atm pressure,
 what mass of material am I injecting?  
(R=0.082 L atm/mole K, MWt of CHCl3 = 119.4 gm/mole)








2.  What effect would failure to completely fill the column with Tide have on the
efficiency of separation of the GC?  Why?






3.  Would it be possible to detect compounds not containing a halogen (Cl, Br, I) 
using a Beilstein detector?  Explain.





4.  The number of theoretical plates, N, is a measure of efficiency of a GC column.   
Calculate the peak widths, wB, for a substance run on two different columns, one 
with N=70.0, the other with N=7000., assuming the retention time, tR, is 100.0 sec 
for both columns.      N=16(tR/wB)2







5.     Calculate how the increase in N will affect the peak height, H, for the substance
 above if identical amounts (Areas) are injected into the two different columns?
 A=1/2 wB(H)