Make: Shimadzu
Model: UV-2450
Principle
Ultraviolet-Visible spectroscopy is working based on the principle of Beer Lambert’s law. It involves, absorbance is directly proportional to intensity of the colour and thickness of the medium.
Ultraviolet light: wavelengths between 190 and 400 nm
Visible light: wavelengths between 400 and 800 nm
Sample preparation
After dissolution of sample to adjust pH is 0.7-1.3 using buffer solutions, then add 1, 5-diphenylcarbazide reagent for colour development. The intensity of the coloured sample was measured by UV-Visible spectrophotometer.
Applications
For Hexavalent chromium Analysis
Strengths
· Accurate determination
· UV-VIS spectrophotometer is the basic instrument
· Determination of maximum elements in periodic table
· Cost of maintained is low
Limitations
· Time taken for analysis
· At a time one parameter only it measures
· Colouring reagents are needed
How many decimal places does the unit give for results when used for absorbance?
This unit has readout to 3 decimal places. However this unit been discontinued and has been replaced with the 83059-10, which will also provide a readout 3 decimal points.
Is it a single or dual beam?
This is a dual beam instrument
What is the minimal volume of sample to read in the spectrophotometer?
This unit uses standard 10 mm cuvettes. If very small sample size are a concern, the thermo Nano-Drop uses as little as 0.5 microliters