A reference solution is used to calibrate the scale. A reference solution is the same as the solution to be analyzed except that it must have zero concentration of the absorbing species.
Place the reference solution in the sample compartment and use the transmittance/absorbance control knob to set the meter to 100%T (0 absorbance).
It is a good idea to recheck the maximum absorbance after setting the zero absorbance to verify that the instrument is working properly.
Click on the knob in the image below used to set the 100%T when a reference solution is in the spectrometer.
Correct! This is the control knob to adjust the spectrometer to 100%T when a reference solution is placed in the spectrometer.
The knob you clicked on is the power switch/zero %T knob. This knob is used to set the 0%T when the cell compartment is empty.
Please try again. You have not clicked on a knob, please try again.
The knob you clicked on is used to set the wavelength of the light that passes throught the sample.
You have clicked on the cell compartment. The cell compartment is where you place your sample.
Click on the knob in the image below used to set the 100%T when a reference solution is in the spectrometer.