UV and visible spectroscopy is a widely used analytical technique that involves the interaction of ultraviolet and visible light with molecules. The range of UV spectroscopy is typically between 100 nm and 400 nm, while the range of visible spectroscopy is between 400 nm and 700 nm.
UV and visible spectroscopy involves the use of a spectrophotometer, which measures the amount of radiation that is absorbed by a sample at different wavelengths.
A sample is placed in a cuvette, and the spectrophotometer measures the amount of radiation that passes through the sample. The amount of radiation that is absorbed by the sample is determined by comparing the intensity of the radiation that is transmitted through the sample to the intensity of the radiation that is transmitted through a reference sample.
UV and visible spectroscopy is based on the interaction of electromagnetic radiation with molecules. When a molecule absorbs radiation, it undergoes a transition from a lower energy state to a higher energy state. The amount of energy required for this transition depends on the nature of the molecule and the type of radiation that is absorbed.
The UV range is a part of the electromagnetic spectrum that has shorter wavelengths and higher energies than visible light. The UV range starts at 100 nanometers and extends to 400 nanometers. UV radiation can be further divided into three regions based on wavelength: UVA (320-400 nm), UVB (280-320 nm), and UVC (100-280 nm).
In UV spectroscopy, The sample is exposed to UV light, and the amount of light absorbed or transmitted by the sample is measured.
The absorption of UV light by molecules can occur through electronic transitions, which involve the movement of electrons from one energy level to another.
UV spectroscopy is particularly useful for studying conjugated systems, which are molecules that contain alternating double and single bonds. These systems have a large number of electrons that can be involved in electronic transitions, leading to strong UV absorption.
The visible range is a part of the electromagnetic spectrum that is visible to the human eye. It is the portion of the spectrum that ranges in wavelength from approximately 400 to 700 nanometers (nm), and corresponds to the colors of the rainbow: violet, blue, green, yellow, orange, and red.
The visible range can be further divided into different colors based on their wavelength. The shortest visible wavelength is violet, which has a wavelength of approximately 400 nm, while the longest is red, which has a wavelength of approximately 700 nm. Other colors in between include blue (approximately 450-500 nm), green (approximately 500-570 nm), yellow (approximately 570-590 nm), and orange (approximately 590-620 nm).
UV and visible spectroscopy are two powerful analytical techniques that are used to study the interaction of electromagnetic radiation with molecules. The UV range typically covers wavelengths from 100 to 400 nm, while the visible range covers wavelengths from approximately 400 to 700 nm. Both ranges have important applications in a wide range of fields, including pharmaceutical, biochemistry, organic chemistry, and optics.
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