Quiz 15 Flashcards
- What is absorbance in spectrophotometry?
nonlinear function of light power
measured quantity
how much light is absorbed by the sample
all of the above
all of the above
- Light emission methods
Fluorescence (X-ray - UV)
Nuclear Magnetic Resonance (NMR)
Chromatography
all of the above
all of the above
- Adjustable wavelength selectors are called
monochromators
photomultiplier tube (PMT)
light sources
detectors
monochromators
- The near infrared (IR) wavelength range is
190-400 nm
400-750 nm
750-2500 nm
190-750 nm
750-2500 nm
The infrared range covers 700-1000 nm (wavelength), or 14,286-12,800 cm-1 (wavenumber), and ultraviolet radiation has wavenumbers above these, approximately, 25,000 – 50,000 cm-1, or 100 to 400 nm (wavelength).
- What is the path of light through a spectrophotometer?
meter, photodetector, filter, sample, light source
meter, filter, sample, photodetector, light source
light source, filter, sample, photodetector, meter
light source, sample, filter, photodetector, meter
light source, filter, sample, photodetector, meter
- Most significant use of infrared (IR) spectrophotometer?
structural analysis
molecular weight
atomic structure
separation of compounds
structural analysis
- Basically, what is the function of an absorption spectrum?
converts light energy into electrical energy
graph of chemical relating absorbance to concentration
graph of chemical relating the absorbance to wavelength
amount of radiation retained by a sample
graph of chemical relating the absorbance to wavelength
- Beer’s law states that
Absorbance is proportional to both the path length and concentration of the absorbing species
Absorbance is proportional to the log of the concentration of the absorbing species
Absorbance is equal to radiant power entering over radiant power leaving the solution(Po/P)
Transmittance is inversely proportional with radiant power P
Absorbance is proportional to both the path length and concentration of the absorbing species
- A known amount of a compound, different from analyte, that is added to an unknown.
internal standard
primary standard
reference standard
none of the above
internal standard
- Carried out on glass plates or strips of plastic or metal coated on one side with a thin layer of adsorbent (use natural chemistry).
Gas Chromatography (GC)
Thin-Layer Chromatography (TLC)
High Performance Liquid Chromatography (HPLC)
Liquid Chromatography - Mass Spectrometry (LC-MS)
Thin-Layer Chromatography (TLC)
- Metallic elements are found where in the periodic table?
in the far left-hand and far right-hand groups
in the left-hand and middle groups
in the middle of the table and Group VIII A
only in Groups IA and IIA
in the left-hand and middle groups
- Metals have
both high electrical and high thermal conductivity
low cohesive strength and high luster
high electrical but low thermal conductivity
high luster and low ductility
both high electrical and high thermal conductivity
- Nonmetals are
malleable but not ductile
very reactive with acids
good conductors of electricity
able to form halides, which react with water to form an oxyacid
able to form halides, which react with water to form an oxyacid
- The halogens
will not react with each other
form strong oxyacids of the formula HOX3
are strong electron donors
form strong covalent bonds wit group IA metals
form strong oxyacids of the formula HOX3
- The rise of liquids up very narrow tubes is called
surface tension
capillarity action
viscosity
buoyant force
capillarity action
