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Minor Versionm

by Vishal Bhatt


Turmeric powder is an excellent base-indicator, thanks to its active ingredient, curcumin. See what happens when it interacts with an alkaline substance!

Video Overview

    • Handle acidic substances with care.

    • Do not inhale any powdery material.

  1. Add two spoons of calcium oxide (CaO), also known as lime (or chuna), in a beaker contaning 50ml water .
    • Add two spoons of calcium oxide (CaO), also known as lime (or chuna), in a beaker contaning 50ml water .

    • Add one spoon of turmeric (haldi) to the above beaker and stir it well.

    • Observe the colour of the mixture.

    • Take a plastic bottle without cap and cut in the middle to get two halves.

    • Place the upper half of the bottle inverted on the lower half.

    • Place a filter paper in the inverted part of the bottle. This acts like a funnel.

    • Transfer the entire mixture to the empty bottle through the funnel.

    • Take the filter paper out from the funnel.

    • Put a few drops of vinegar on the vermilion collected on the filter paper using a dropper .

    • Apart from the yellow coloured sample, created by the addition of vinegar (or any acid), collect the remaining vermilion and let it dry for 2hrs.

    • The vermilion becomes a lovely deep red powder: kumkum

    • Mix the lime with water thoroughly before adding the turmeric.

    • Make sure the quantities of turmeric and lime used are comparable.

    • What will happen if you increase the amount of turmeric compared to lime or vice-versa?

    • How much vinegar did you need to turn 1ml of vermilion back to yellow?

    • What are the other household acids you could use instead of vinegar?

    • Test various fruits and vegetables at home: potato, tomato, pumpkin, banana etc and figure out if any of them are alkaline.

    • Do the same with inedible substances like soap, shampoo, conditioner, toothpaste etc.

    • Turmeric cannot detect acids; can you think of a home-made acid indicator?

Finish Line

Procheta Mallik

Member since: 05/02/2017

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