Introduction: Onion Natural PH Indicator

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We can easily make a pH natural indicator from red onion. I have also tested it with different acids and bases and uploaded a video at the end.

Supplies

1x Red Onion
Boiling water
Acids and Bases for testing

(Acids- Citric acid, Lemon, Vinegar etc.)

(Bases- Window cleaner, Baking soda, Detergent etc.)

Step 1: Chop an Onion Into Small Slices

Step 2: Boil Some Water, and Add It to a Container

Step 3: Put the Sliced Onion in the Water and Let the Water Cool Down

Step 4: After Cooling Down, the Water Gets Coloured

Step 5: The PH Indicator Is Ready! Strain and Use It

The solution turns red when added to an acid, and turns green when added to a base. Darker the colour, the more is it acidic or basic

Step 6: Testing With Acids and Bases

Step 7: Acids and Bases I Used

Bases- 1,2,3

Acids- 4,5,6

1- Window Cleaner, Color changes to Green- pH 11

2- Baking soda, Color changes to Light Green- pH 8

3- Detergent, Color changes to Yellowish-Green-pH 10

4- Citric Acid, Color changes to Red-pH 2

5- Vinegar, Color changes faintly to Red-pH 3 (Depends on the type of vinegar)

6- Lemon, Color changes to Light Red-pH 2