"Wow Amazing Colorful, It's Magic!" "No, This is Science!"
Today with this tutorial you can learn easy way to create pH indicator with red cabbage!
This fantastic vegetable has good property for indicate with different colours the type of pH solution, red when the liquid is acid (pH low, like vinegar) and green or blue when alcaline (pH 14, like Sodium hydroxide). This proprerty is due to a pigment inside the juice: the anthocyanins
For make this instructables you need only the red cabbage and a source of heat for extract the juice.
If you prefer The video check it HERE
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Step 1: Start!
Grab a chopping board and cut the Cabbage in tiny piece, this help the juice to get out in the next step, after, put all product in a pan
Step 2: Start to Boil
You only add 1 liter of tap water with your red cabbage and place the pan on the source of heat.
When the water start to boil you can see the water becames dark purple, now you can stop the heat and remove the pan from the fire.
Step 3: Filter
Remove all solid part from the liquid and after filter with a strainer.
You can see a very dark purple, but for regular use you need to dilute with the water, this is the neutral indicator. There is different type of cabbage and the color can change of dark or light , for my perfect indicator I have diluted with 1/3 part of concentrate indicator and 2/3 part of tap water and obtained light purple color
Step 4: Test It!
Ok now the best part of tutorial! the test.
For make this you only need different type of product:
Vinegar PH acid
Lemon juice PH acid
Baking Soda PH alcaline
Ammonia PH alcaline
You only test your product with add few drops of the liquid you want to test in the indicator, and you see the color of the indicator change, red if acid and green or blue if alcaline!
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