Infrared Spectroscopy: Pre-Lab Quiz

Click on the correct answer


1	*What is vibrational spectroscopy?*
		IR in an earthquake
		When you shine a flashlight through a prism and shake it
		A class of spectroscopic techniques which analyzes molecular motions
		The study of epileptic ghosts
		Infrared spectroscopy

2	The picture to the right is a representation of . . .
		A spring with two balls attached to it
		A circuit diagram of two point charges connected by a resistor
		A short carbon chain with large endgroups
		A simple harmonic oscilator
		Two circles and a squiqqly line

3	Which of the following will oscillate the fastest?
		A large mass on a weak spring
		A large mass on a stiff spring
		A small mass on a stiff spring
		A small mass on a weak spring


4	A simple harmonic oscillator may absorb energy . . .
		anytime.
		when the frequencies match exactly.
		when the amplitudes are the same.
		at no time.


5	In the past, IR spectra had to be aquired one wavelength at a time, which took a long time. Why can we collect spectra so quicly today?
		The Fourier Transfer Algorithm allows us to scan all frequencies at once.
		Light is faster today that it used to be.
		Some guy figured out a better way.
		We are smarter than the people in the past.


6	Which of the following is not an IR vibrational mode?
		stretching
		scissoring
		rocking
		rolling
		wagging

7	Where does a carbonyl (C=O) stretch appear in an IR spectrum?
		740 - 720
		1870 - 1650
		3640 - 3250
		650 - 600
		1160 - 1030

8	When casting a film on water, why is it improtant to choose a solvent which is less dense than water?
		So that the solvent and water don't mix.
		So the water does not evaporate before the solvent.
		So you can form a film.
		So the solution will "float" on top of the water.


9	Why is it improtant to where gloves when handling salt plates?
		There might be some toxic chemical left on the salt plate.
		There is moisture on your fingers which will damage the salt plate.
		The solvents used are often carcinogenic.
		The oils and dirt on your fingers will affect your spectrum.
		All of the above.

10	Why is it important to aquire a background spectrum?
		So you don't see carbon dioxide in your spectrum.
		So you don't have peaks characteristic of your substrate in your spectrum.
		Because a picture always looks better on a nice background.
		All of the above
		A and B only