Font size
WorksheetsInstrumentation in Chemistry
Total questions: 10
Worksheet time: 6mins
For what purpose do scientists use Infrared Spectrophotometry?
Identify organic compounds
Identify inorganic compounds
Determine concentration of an absorbing compound
Separate & identify small quantities from mixtures
For what purpose do scientists use Ultraviolet and Visible light spectrophotometry?
Identify organic compounds
Identify inorganic compounds
Determine concentration of an absorbing compound
Separate & identify small quantities from mixtures
For what purpose do scientists use nuclear magnetic spectroscopy?
Determine the fine structure of a compound containing hydrogen
Determine fine structure of compounds that do not contain hydrogen
Determine concentration of an absorbing compound
Separate & identify small quantities from mixtures
For what purpose do scientists use paper chromatography?
Determine molar mass of a compound
Determine fine structure of organic compounds
Separate chemicals in a mixture for identification purposes
Separate chemicals in a mixture for further processing of each
Abs=4.301[conc]+.002 Pictured is a Beer-Lambert calibration curve for chrysin in a compatible solvent. The best fit line has the equation shown above. What is the concentration of the compound if absorbance is 0.83?
(a)
When running a gas chromatography separation, what is the typical volume of mixture or liquid that is injected into the device?
1 milliliter
1 microliter
1 deciliter
1 picoliter
What is the most important criterion for choosing a carrier gas for a gas chromatography investigation?
it must never be air
it must be completely inert
it must have the lowest possible molar mass
it must not react with any of the chemicals or solvents being run through the device
In this IR spectrophotometer trace of acetone, you can clearly see the "peak" of absorbance around 1750 cm-1, showing the typical carbonyl absorbance. Which of these molecules is acetone?
Can an investigator use gas chromatography to determine the approximate percentage of a compound in a mixture of two compounds?
No
Yes, if there is a difference in the rate at which the compounds move in the column
Yes, if the compounds in the mixture react with each other
Yes, but only if the two compounds are isomers of each other, and so have the same molar mass
What type of electromagnetic radiation is used in nuclear magnetic resonance spectrometry?
UV-visible waves
Infrared waves
X-ray
radio waves
