WorksheetsFTIR
Total questions: 32
Worksheet time: 30mins
The intensity of an absorption band is always proportional to which of the following factor?
Atomic population
Molecular population of the initial state
Molecular population of the final state
Temperature
On which factors the vibrational stretching frequency of diatomic molecule depend?
Force constant
Atomic population
Temperature
Magnetic field
The vibrations, without a center of symmetry are active in which of the following region?
Infrared but inactive in Raman
Raman but inactive in IR
Raman and IR
Inactive in both Raman and IR
1700 cm-1, and 1200 cm-1. Identify the compound.
I. aldehydes
II. esters
III. ethers
What do spectroscopes do?
Collect light to identify elements
Refract light
Absorb light
Transmit light
FTIR is
Fourier Transform Infrared surface
Fourier Transform Infrared spectrophotometer
Field Transform Infrared spectrophotometer
Fourier Transmission Infrared spectrophotometer
Finger print regin is -------cm-1
1000-1600
2400-3500
200-1700
500-1500
Which type of electromagnetic radiation has the least energy?
Infrared
Ultraviolet
Microwaves
Radiowaves
What is the effect of greater polarity on IR absorption?
The absorption becomes weaker
The absorption becomes stronger
The absorption becomes more charged
The absorption occurs at a smaller wavenumber
Which functional group gives an absorption at 1750cm-1
carbonyl
amines
ether
none of the above
What is the purpose of Fourier Transform Infrared Spectroscopy (FTIR)?
To measure the intensity of visible light
To analyze the absorption of infrared radiation
To study the emission of ultraviolet radiation
To detect the presence of microwaves
Which region of the electromagnetic spectrum does Fourier Transform Infrared Spectroscopy (FTIR) focus on?
Visible light region
Ultraviolet region
Infrared region
X-ray region
How does Fourier Transform Infrared Spectroscopy (FTIR) differ from Raman Spectroscopy?
FTIR uses visible light, while Raman uses ultraviolet light
FTIR analyzes absorption, while Raman analyzes emission
FTIR focuses on the infrared region, while Raman focuses on the microwave region
FTIR measures intensity, while Raman measures frequency
What is the significance of the fingerprint region in an FTIR spectrum?
It represents the unique pattern of a molecule
It indicates the presence of impurities
It shows the intensity of the absorption bands
It measures the frequency of the molecular vibrations
How does the presence of water affect the FTIR spectrum of textiles?
It enhances the vibrational modes of the textile fibers
It suppresses certain absorption peaks
It shifts the entire spectrum to higher wavenumbers
It has no impact on the FTIR spectrum
Why is baseline correction important in analyzing FTIR spectra of textiles?
It helps in identifying the type of textile used
It removes noise and artifacts for accurate peak analysis
It enhances the color contrast of the spectrum
It reduces the overall intensity of the absorption bands
FTIR is a non-destructive analysis.
TRUE
FALSE
In FTIR, liquid samples are mixed with nujol and sandwiched between two NaCl disc.
TRUE
FALSE
In FTIR sample preparation, solid sample are mixed with KBr and compressed at 800kPa to make a KBr disc.
TRUE
FALSE
HeNe laser in FTIR is used internally to improve wavelength accuracy.
TRUE
FALSE
FTIR is less satisfactory quantitative tool because (>1answer)
Frequent deviation from Beers Law
Lower sensitivity
Easy to operate
Measurements are less precise
Which are the units usually shown on the x- and y-axis of a IR spectrum?
ABS & wavelength
ABS & wavenumber
Transmittance & wavelength
Transmittance & wavenumber
14. Why is potassium bromide (KBr) used in FTIR sample preparation?
A. It fluoresces under IR light
B. It absorbs strongly in the IR region
C. It is IR transparent
D. It stabilizes the sample
15. When conducting quantitative analysis by FTIR, which law describes the relationship between absorbance and concentration?
A. Raoult’s Law
B. Beer–Lambert Law
C. Dalton’s Law
D. Henry’s Law
