Podcast
Questions and Answers
What field of study involves the interaction between electromagnetic radiation and matter?
What field of study involves the interaction between electromagnetic radiation and matter?
Spectroscopy
What type of energy is transmitted through space at enormous velocities?
What type of energy is transmitted through space at enormous velocities?
Electromagnetic radiation
In a wave, what is the length of the electrical vector at the maximum point called?
In a wave, what is the length of the electrical vector at the maximum point called?
Amplitude (A)
What is the linear distance between successive maxima or minima of a wave called?
What is the linear distance between successive maxima or minima of a wave called?
What is the term for the number of oscillations of a field per second?
What is the term for the number of oscillations of a field per second?
What are the packets of energy that make up electromagnetic radiation called?
What are the packets of energy that make up electromagnetic radiation called?
What is a functional group that absorbs light, such as C=C, C=O, N=N, and N=O, called?
What is a functional group that absorbs light, such as C=C, C=O, N=N, and N=O, called?
What is a functional group that does not absorb in the UV/VIS region called?
What is a functional group that does not absorb in the UV/VIS region called?
What is unwanted light of wavelengths that differ from the target wavelength called?
What is unwanted light of wavelengths that differ from the target wavelength called?
Which type of spectrophotometer is influenced by the instability of the light source?
Which type of spectrophotometer is influenced by the instability of the light source?
Which lamp is used for measurements in the ultraviolet region (190 to 350 nm)?
Which lamp is used for measurements in the ultraviolet region (190 to 350 nm)?
Which lamp is used for measurements in the visible region (350 to 900 nm)?
Which lamp is used for measurements in the visible region (350 to 900 nm)?
Which lamp provides a continuous source in the ultraviolet region?
Which lamp provides a continuous source in the ultraviolet region?
A spectrophotometer generally has an entrance _____ and an exit _____.
A spectrophotometer generally has an entrance _____ and an exit _____.
What happens to the light intensity and resolution when the slit width is increased?
What happens to the light intensity and resolution when the slit width is increased?
Which type of cuvette has a wide range from 190 to 2500nm and is stable with most acids, bases, and organic solvents?
Which type of cuvette has a wide range from 190 to 2500nm and is stable with most acids, bases, and organic solvents?
Which type of cuvette is useful in the region of 350 - 2000 nm?
Which type of cuvette is useful in the region of 350 - 2000 nm?
Which type of cuvette is disposable and molded from polystyrene methacrylate and other transparent plastics?
Which type of cuvette is disposable and molded from polystyrene methacrylate and other transparent plastics?
What type of semiconductor element is used to convert light energy into electrical energy?
What type of semiconductor element is used to convert light energy into electrical energy?
Which type of spectroscopy is more suitable for characterization, but not for structural elucidation?
Which type of spectroscopy is more suitable for characterization, but not for structural elucidation?
Which type of spectroscopy has taken a more important role in quantitation, rather than structural determination?
Which type of spectroscopy has taken a more important role in quantitation, rather than structural determination?
Which type of liquid is measured by the transmittance method?
Which type of liquid is measured by the transmittance method?
Which type of liquid is measured by the transmittance or reflectance method (by integrating sphere)?
Which type of liquid is measured by the transmittance or reflectance method (by integrating sphere)?
Which type of liquid is measured by the reflectance method (by integrating sphere)?
Which type of liquid is measured by the reflectance method (by integrating sphere)?
What type of samples are measured by the reflectance method (by integrating sphere or specular reflectance accessories)?
What type of samples are measured by the reflectance method (by integrating sphere or specular reflectance accessories)?
What type of calibration uses only 1 calibration standard and is mainly applied to a pass/fail situation?
What type of calibration uses only 1 calibration standard and is mainly applied to a pass/fail situation?
Which type of calibration requires at least 2 calibration standards and is a more accurate method?
Which type of calibration requires at least 2 calibration standards and is a more accurate method?
How many calibration standards are generally obtained by performing serial dilution?
How many calibration standards are generally obtained by performing serial dilution?
What is the ideal absorption unit range for performing spectrum scanning of standards to determine the maximum absorption peak wavelength?
What is the ideal absorption unit range for performing spectrum scanning of standards to determine the maximum absorption peak wavelength?
What spectroscopic technique examines the derivatives of absorbance with respect to wavelength?
What spectroscopic technique examines the derivatives of absorbance with respect to wavelength?
What is used for measurement of diffuse and total reflectance, diffuse and total transmittance?
What is used for measurement of diffuse and total reflectance, diffuse and total transmittance?
What method separates the solute from the stationary or mobile phase based on the difference in interaction?
What method separates the solute from the stationary or mobile phase based on the difference in interaction?
In what year was high performance liquid chromatography 'born'?
In what year was high performance liquid chromatography 'born'?
What is the term for the localization of electrons within a molecule, which can cause molecules to have negative and/or positive poles?
What is the term for the localization of electrons within a molecule, which can cause molecules to have negative and/or positive poles?
What is polarity of the Stationary phase in Normal-Phase/Absorption Chromatography?
What is polarity of the Stationary phase in Normal-Phase/Absorption Chromatography?
What is the polarity of the Mobile phase in Normal-Phase/Absorption Chromatography?
What is the polarity of the Mobile phase in Normal-Phase/Absorption Chromatography?
What is the polarity of the Stationary phase in Reversed-Phase Chromatography?
What is the polarity of the Stationary phase in Reversed-Phase Chromatography?
What is the polarity of the Mobile phase in Reversed-Phase Chromatography?
What is the polarity of the Mobile phase in Reversed-Phase Chromatography?
Which chromatography method separates compounds by molecular size (bulkiness)?
Which chromatography method separates compounds by molecular size (bulkiness)?
Flashcards
Spectroscopy
Spectroscopy
The study of the interaction between electromagnetic radiation and matter.
Electromagnetic radiation
Electromagnetic radiation
The type of energy transmitted through space at enormous velocities.
Amplitude (A)
Amplitude (A)
The length of the electrical vector at the maximum in the wave.
Wavelength (λ)
Wavelength (λ)
Signup and view all the flashcards
Frequency (n)
Frequency (n)
Signup and view all the flashcards
Photons/Quanta
Photons/Quanta
Signup and view all the flashcards
Chromophore
Chromophore
Signup and view all the flashcards
Auxochromes
Auxochromes
Signup and view all the flashcards
Stray light
Stray light
Signup and view all the flashcards
Single-Beam Spectrophotometer
Single-Beam Spectrophotometer
Signup and view all the flashcards
Double-Beam Spectrophotometer
Double-Beam Spectrophotometer
Signup and view all the flashcards
D2 lamp
D2 lamp
Signup and view all the flashcards
Halogen lamp
Halogen lamp
Signup and view all the flashcards
Quartz/fused silica cuvette
Quartz/fused silica cuvette
Signup and view all the flashcards
Plastic cuvette
Plastic cuvette
Signup and view all the flashcards
Photodiode
Photodiode
Signup and view all the flashcards
UV/Vis spectroscopy
UV/Vis spectroscopy
Signup and view all the flashcards
Translucent liquid
Translucent liquid
Signup and view all the flashcards
Opaque liquid
Opaque liquid
Signup and view all the flashcards
Multipoint calibration
Multipoint calibration
Signup and view all the flashcards
Derivative spectroscopy
Derivative spectroscopy
Signup and view all the flashcards
Chromatography
Chromatography
Signup and view all the flashcards
High performance liquid chromatography
High performance liquid chromatography
Signup and view all the flashcards
Polarity
Polarity
Signup and view all the flashcards
Size Exclusion Chromatography
Size Exclusion Chromatography
Signup and view all the flashcards
Study Notes
Spectroscopy
- Spectroscopy studies the interaction between electromagnetic radiation and matter.
- Electromagnetic radiation is energy transmitted through space at high velocities.
Electromagnetic Radiation Properties
- Amplitude (A): Maximum length of the electrical vector in a wave.
- Wavelength (λ): Distance between successive wave maxima or minima.
- Frequency (n): Number of oscillations per second.
- Photons/Quanta: Electromagnetic radiation is made of packets of energy.
Key Molecules/Functional Groups
- Chromophores: Functional groups (e.g., C=C, C=O) that absorb light.
- Auxochromes: Functional groups that do not absorb UV/Vis light.
Spectrophotometer Types and Components
- Single-Beam Spectrophotometer: Affected by light source instability.
- Double-Beam Spectrophotometer: Not affected by light source instability.
- Light Sources: D2 lamp (UV region, 190-350nm), Halogen lamp (visible region, 350-900nm), Deuterium/Hydrogen Discharge Lamp (continuous UV source).
- Slits: Spectrophotometers have entrance and exit slits. Wider slits increase light intensity but decrease resolution. Narrower slits decrease intensity but improve resolution.
- Cuvettes: Quartz/fused silica (190-2500nm), silicate glass (350-2000nm), and plastic (disposable).
- Detector: Photodiode converts light to electrical energy using the photovoltaic effect.
Spectroscopy Applications and Considerations
- UV/Vis Spectroscopy: Useful for quantitation, not structural elucidation.
- Sample Types: Transparent liquids (measured by transmittance), translucent liquids (transmittance or reflectance, using integrating sphere), opaque liquids (reflectance, using integrating sphere), solids (reflectance, using integrating sphere or specular reflectance accessories).
- Calibration: Single-point calibration uses one standard (simpler, but less accurate, useful for pass/fail). Multipoint calibration uses multiple standards (more accurate, allows for error detection). Serial dilutions (3-5 standards) are used to create calibration standards. Standards concentrations should be between 0-0.4 absorbance units (specific to machine).
- Advanced Techniques: Derivative spectroscopy calculates derivatives of absorbance with respect to wavelength. Integrating spheres (ISR) measure diffuse and total reflectance/transmittance.
Chromatography
- Chromatography separates solutes based on interaction differences with mobile/stationary phases.
- High-performance liquid chromatography (HPLC) was developed in 1969.
- Polarity: Molecules can have negative and positive poles.
- Chromatography Types:
- Normal-phase chromatography uses a highly polar stationary phase, and a less polar mobile phase.
- Reversed-phase chromatography uses a low polarity stationary phase, and a highly polar mobile phase.
- Size Exclusion Chromatography (SEC) separates by molecule size and bulkiness.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Spectroscopy explores how electromagnetic radiation interacts with matter. Electromagnetic radiation transmits energy through space at high speeds. Key aspects include amplitude, wavelength, frequency, and photons. Functional groups like chromophores and auxochromes play a crucial role.
