UNIT-3 SPECTROSCOPY AND CHROMATOGRAPHY

The source of UV light is

• Nernst globar

• Hg lamp

• Tungsten filament

• H2 lamp

The functional gruoup of a molecule can be characterised by using

• UV spectroscopy

• Mass spectroscopy

• IR spectroscopy

• NMR spectroscopy

The type of electrons present in carbonyl compound are

• Sigma electrons

• Pi electrons

• Non bonding electrons

• All of these

In UV spectroscopy, the functional group capable of electronic transition is known as

• Auxochrome

• Chromophore

• Monochrome

• Auxillary group

Mostly used spectroscopic detector in HPLC is

• NMR

• UV

• IR

• Mass

IR radiation can bring change in

• Electronic excitaiton

• Vibrational change

• Change in rotational levels

• Molecule fragmentation

In order to be IR active, the molecule should have

• Dipole moment

• Double bond

• Triple bond

• Lower energy of excitaiton

Incandescent lamp is a source of

• Radio waves

• Micro waves

• IR energy

• UV energy

Which of the following can give nmr signals

• 1H

• 15N

• 13C

• All of these

The reference compound used in NMR spectroscopy is

• TMS

• DMS

• SMS

• CDCl3