Potassium dichromate in Sulphuric Acid (430 nm)
| Description | Potassium dichromate filter, liquid filter, certified |
| Use | Assessment of photometric accuracy (absorbance) in the Vis range (measuring wavelength 430 nm) with a spectral bandwidth of 2 nm or less |
| Material | 0.06% potassium dichromate dissolved in sulphuric acid and sealed in Hellma precision cells made from quartz SUPRASIL® |
667-UV17 0.06% Potassium dichromate dissolved in sulphuric acid
Fifth revision of European Pharmacopeia stipulates also checking the photometrical accuracy of the spectrophotometer at a wavelength in the visible region (430 nm) besides the checking in the UV region. The testing has to be carried out by means of a solution of 0.06% potassium dichromate dissolved in sulphuric acid. The absorbance value of the filter is determined at a wavelength of 430 nm and is specified in the certificate. It should be noted that the measurement is carried out with the filter 667-UV8 (0.01 N sulphuric acid) in the reference beam path. Measured values of the reference filter are separately displayed.
Typical spectrum of a 0.06 % potassium dichromate solution
| Wavelength (nm) | Specific Absorption A 1 %1 cm | Maximum Tolerance A 1 %1 cm |
| 430 | 15,9 | 15,7 to 16,1 |