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Why is the wavelength 275 nm used to measure absorbance of caffeine?
Wiki User
∙ 12y ago
Different substances have their characteristic behavior for different wavelengths; I assume caffeine easily absorbs that particular frequency.
Wiki User
∙ 12y ago
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What is the purpose of wavelength scan?
Wavelength scans measure the absorbance and emission of light through a sample. Absorbance is proportional to concentration and a wavelength scan can be used to determine concentrations of a sample.
What dose wavelenght measure?
Distance from one crest to the next crest of a wave.
What equation is used to measure wave speed?
speed= frequency x wavelength
What is a unit of measuring wavelength of light?
The SI unit is meter. But nanometer and angstrom are commonly used units to measure the wavelength of light.
What does a spectrometer measure?
A spectrometer measures properties of light of a specific part of the wavelength. It is often used to measure the intensity of a light.
What is the purpose of wavelength scan?
Wavelength scans measure the absorbance and emission of light through a sample. Absorbance is proportional to concentration and a wavelength scan can be used to determine concentrations of a sample.
What is the purpose of the blank?
Blank Sample in Spectrophotometry is used to measure the absorbance of light without sample. It is subtracted from the total absorbance for measurement of Absorbance from a sample's absorbance.
What is the purpose of blank samples?
Blank Sample in Spectrophotometry is used to measure the absorbance of light without sample. It is subtracted from the total absorbance for measurement of Absorbance from a sample's absorbance.
Why caffeine used for calibration?
Caffeineis dule absorbance,it gives multiwavelength responds like 205,245,273.
What is the optimum wavelength of light absorbed by chlorophyll and why?
The optimum wavelength of chlorophyll is 430nm (in a light spectrum of 380nm-750nm going in 10 incements) We did a lab and it required us to determine the optimum wavelength of chlorophyll by testing the absorbance of light in 10nm increments from 380nm-750nm. Optimum wavelength is the wavelength of light that is absorbed best by a substance. So when we tested all the wavelngths 380-750 in 10 increments (380,390,400,410,420....) 430 had the highest absorbance. we used a Spec 20 machine to find the absorbance.
What is blank in spectrophotometer?
A blank is used in order to cancel out or zero the absorbance of all the other components in the sample except the component whose absorbance is to be measured. For example, if you want to measure the absorbance of a solute in water, you will use only water as a blank and the spectrophotometer will subtract the absorbance of water from the spectrum when you measure the absorbance of your solute in water.
Why are particular wavelengths used for particular spectrophotometric assays?
A particular wavelength used for particular spectrophotometric assays is based upon the absorbance pecularity of the substance in consideration/used for the assay. That particular substance absorbs at a particular wavelength leaving other things alleviating the chances of background contamination/noise.
Why should the concentration of sample be low in spectrophotometer readings?
When doing reading on a spectrophotometer, the sample being studied is either a color change or a precipitated compound, depending on the wavelength that it is being read. If it is a precipitated compound and it has a very high concentration, then you run the risk of the light being used to measure the absorbance not going through. In which case you have total absorbance but it is inaccurate in helping you determine the concentration of your sample because you are unsure where the concentration limit is for that wavelength, and your sample could possibly be able to absorb more. In which case you still can't calculate the concentration of the sample.
What dose wavelenght measure?
Distance from one crest to the next crest of a wave.
What equation is used to measure wave speed?
speed= frequency x wavelength
What is a unit of measuring wavelength of light?
The SI unit is meter. But nanometer and angstrom are commonly used units to measure the wavelength of light.
What does a spectrometer measure?
A spectrometer measures properties of light of a specific part of the wavelength. It is often used to measure the intensity of a light.
