I get negative value of absorbance of dye solution what can i do?

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Tuhin Khan

Negative absorbance have no physical meaning and is due to experimental error. Search ResearchGate on "negative absorbance" and go through the discussions. If you are still not satisfied with the answers please provide the spectra of yours so we can have a look at it.

Fernando J. Sialana

Phenols typically would change color with changes in pH. I would dissolve the dye in pH 11 and set the absorbance to zero prior to the addition of the substance you want to test.

Harry ten Brink

I would first fully study and the manual try to understand of your spectrophotometer