Abstract

Use of Ipomoea Aquatica Flower as Neutralisation Indicator

Author(s): Mayur C. Shah

Neutralisation titrations play a key role in titrimetric analysis. Nowadays synthetic indicators contribute active role in volumetric neutralization titrations. Industrial production and use of synthetic indicators cause pollution to environment and creates human health problems. The remedy of this is to use natural substrates instead of chemicals to prepare these indicators. The present study deals with this aspect in which a natural neutralisation indicator was prepared from flower extract of Ipomoea aquatica and standardized for neutralization titrations. Flowers of Ipomoea aquatica having pink or pale lilac colour. The 10% w/v water extract of Ipomoea aquatica shows different colours at different pH i.e. pink (between 0 and 8.0 pH); green (8.0 to 11.0 pH); greenish yellow (above 11.0 pH) in pH metric titrations of 0.1 M HCl with 0.1 M NaOH and CH3COOH with NaOH, whereas it failed to produce color change at the end point in NH4OH and HCl titration.