TRAVISTRA

 GAS CHROMATOGRAPHY It is used for the separation as well as analysis of gaseous mixture and volatile organic compounds. Principle The components of a mixture are separated depending upon the extent of adsorption or partition of the stationary phase and at the rate at which the component is carried out by the mobile phase.  The mobile phase is a gas like Argon, Nitrogen, Helium, or hydrogen. The stationary phase may be solid or liquid. If the stationary phase consists of a solid material like silica, alumina, then chromatography is termed as Gas Solid Chromatography (GSC), and if the stationary phase is a liquid held as a thin layer on a solid support, then the technique is known as Gas-Liquid Chromatography (GLC)GSC- adsorption. GLC- partition INSTRUMENTATION  Carrier gas: It is allowed to flow through the system, carrying the sample in the vapor state through the column. It should be chemically inert, suitable for the detector employed, it should give the best column pe...

 IR VIBRATIONAL SPECTROSCOPY  It involves the transition between vibrational energy levels of a molecule. It arises due to the change in dipole moment with the vibration of a bond.  The vibrational spectra are given by the EM radiations in the IR region of range 500-4000cm-1  This type of spectrum is given by diatomic molecules with permanent dipole moments like HCl, H2O, and molecules with fluctuating dipole moments like CO2. These are IR-active molecules. Compounds which are IR inactive are H2 , O2, N2, Cl2  It is also called vibrational rotational spectrum since the rotational energies are smaller than vibrational energies so both vibration and rotation occur simultaneously.  It is used to establish the identity of a compound or determine the structure of a new compound. It can also predict the functional groups which absorb at definite frequencies. PRINCIPLE The movement of atoms and the chemical bonds (vibration) is like a spring and ball. The charact...