BBM. I'm going to do my best to answer your question about the GC/MS without going into too much detail. Gas Chromatography is a method of separating and identifying chemicals based on their boiling points and their polarity. To use a GC, you inject a small amount of a sample into an injection port where the sample is vaporized and loaded onto a column. The mobile phase, usually a noble gas, carries the sample through the system (the heated column) and allows the sample to interact with the stationary phase. The stationary phase is the substance that lines the inside of the column (this is what the sample with interact with). In chemistry, similar substances will bond with similar substances....we say that "like dissolves like". A polar component of the sample will bond with a polar stationary phase within a column, whereas a non-polar component of the sample will not (and vice versa). The components of the sample that bind with the stationary phase will stay on the column longer than the components that are not bound to the stationary phase; this means that the non-binding components will travel through the column and be eluted more quickly than the binding components will be. In order to cause the bound components to be eluted from the column in a reasonable amount of time, it is heated. Controlling the temperature of the GC also serves the purpose of separating the components of the sample by their boiling points. Smaller molecules will reach their boiling point more quickly than larger molecules will, so the small molecules will move through the system more quickly. Therefore, GC analysis will allow for the separation of components in a sample based on both boiling point of a component and on its polarity (similarity to the stationary phase).
Once a component reaches the end of the column and is eluted, a detector will graph the intensity of the response against the time at which the component was eluted (called the retention time). Different compounds will be eluted at different retention times, so the intensity of the peak at a given retention time will represent the concentration of the corresponding compound (or sample component). This graph is called a chromatogram. There are many different types of detectors that can be coupled with a GC, one of which is called a Mass Spectrometer. How a Mass Spec works is WAAAAAY beyond the scope of what I can explain simply and it isn't really important in this context. Mass Spec can be used as a detector with an HPLC or an IPC as well as a GC....the other instrument does the separation and the MS is just the detector. Anyhow, back to my main point, chloroform is chloroform is chloroform....it's the same molecule no matter how it is made. If it weren't chloroform, the GC would have eluted it at a different retention time...make sense? Hope this helps answer your question.
I'd say that's a great guess on your part, someone spit chewing tobacco in it. The bottle was found in the trash in the car along with the tobacco can, right? if so, makes perfect sense.
) cycle, leaving nothing of evidentary value. My guess is that they can find other sources to compare, like those two compounds found in the trunk (can't think of the names at this point, been sleuthin' all day :crazy
