CONCLUSION
All pH indicators changes colors depending upon whether they donate or accept protons.
Therefore, pH indicators are themselves acids or bases. The selective of rose anthocyanin as
natural dyes to indicate specific pH levels was based on its chemical changes. In this work,
the flower extract of rose are suggested as pH indicator in the form of either solutions. The
Padma S Vankar et al. EJEAFChe , 9.(5), 2010. [875-884]
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pH indicator solutions were prepared from the acidified methanolic extracts of the rose
flower. The different pH leads to color changes in the indicator solutions and it can be used
for teaching elementary chemistry concepts of acid-base titrations. Acidified methanolic
extract of Rosa rosa were prepared and used as new indicators in quantitative analysis of
standardization of NaOH and HCl solutions. Effect of using such natural extracts as
indicators gave quantitative results as compared with conventional indicators with good
agreement.