MURRAYA KOENIGII FRUIT EXTRACT - HERBAL ALTERNATIVE TO SYNTHETIC ACID BASE INDICATORS

Dr. R. F. Pagariya*

ABSTRACT

Indicators used in neutralization titration show well marked changes of colour in certain intervals of pH. Most of these indicators are organic dyes and are of synthetic origin. Today synthetic indicators are the choice of acid-base titrations. But due to environmental pollution, availability and cost, the search for natural compounds as an acid-base indicator was started. The present vocation highlights the exploit of Murraya Koenigii fully ripened fruit extract as a pH indicator in strong acid-strong base, strong acid weak base, weak acid strong base and weak acid-weak base titrations. This natural indicator is easy to prepare. The results showed that the fruit extract of Murraya Koenigii indicator is colourless in acidic solution, while greenish yellow in basic solution. The comparison indicators used in this research were methyl red, methyl orange, phenol red and phenolphthalein. Promising results were obtained when it was compared against standard synthetic indicators. Volumetric titrations between acid and base shows sharp colour change at the equivalence point. The equivalence points obtained match with the equivalence points obtained by standard indicators. Therefore this natural indicator is found to be a very useful, economical, simple, accurate and eco-friendly for acid base titration.

Keywords: Fruit Extract, Murraya Koenigii, Natural indicator, Acid base indicator, Equivalence point.