Allium cepa.L As Acid-Base Indicator

4^th European Chemistry Congress

May 11-13, 2017 Barcelona, Spain

Gan Lui Nam , Koo Thai Hau and Ling Jia Yi

Form 6 centre of SMK Taman Johor Jaya 1, Malaysia

Posters & Accepted Abstracts: Chem Sci J

Abstract :

In this study, a facile and environmentally friendly method was reported for manufacturing of natural acid-base indicator by preparing Allium cepa. L juice, which provided the anthocyannins pigment. The anthocyannins pigment was extracted via boiling process. In detailed, the Allium cepa. L was cut into small fragments. Then, the small fragments of Allium cepa. L was boiled in distilled water in order to extract the anthocyannin pigment. This process was followed by the addition of different solutions, acidic solution, base solution as well as neutral solution were added into separate test tubes filled with extraction of Allium cepa. L juices. The obtained Allium cepa. L juice was then used as the pigment for the acid-base indicator. The pH of the solution can be determined by observing the colour change in the Allium cepa. L juice. The light purplish colour of Allium cepa. L juice turned into red colour when added with hydrochloric acid; its purplish colour of the juice turned into yellow when added with sodium hydroxide; the original colour of Allium cepa. L did not undergo any observable colour change when distilled water is added into it. The Allium cepa. L exhibited excellent colour change property with chemical solutions. These colour changes make the Allium cepa. L be attractive for applications in acid-base indicators. Happy_angel0831@hotmail.com