Experiment: Sauer, neutral oder basisch: Mit Rotkohl-Saft den pH-Wert bestimmen
Swiss Nanoscience Institute
https://www.youtube.com/watch?v=V4Zu2Vvmw8A

Transkript (automatisch erstellt)

0:00 Do you like red cabbage? Whether or not it’s your favorite dish, you can use it to do some really experiments.
0:11 Red cabbage juice can be used to check whether a solution is acidic, neutral or alkaline, and we’re going to show you how.
0:20 First of all, cut the cabbage in half and slice it into thin strips. Then wash it thoroughly under running water.
0:35 Put it in a saucepan, add two liters of water, and cook it well  around 10 minutes.
0:45 You will soon notice that the water has turned blue. Strain it into a measuring cup using a sieve. Now the experiment can really begin.
0:58 Fill several glasses with the red cabbage juice, and find substances that you want to test to find out whether they are acidic, neutral or alkaline
1:10 when dissolved in water. Let’s start with the lemon juice. Pour a few drops into one of the glasses,
1:24 and watch how the violet color changes to red. Now try an effervescent vitamin tablet. Once again, the color changes to red.
1:42 What do you think will happen with vinegar? That’s right – red again. The red color indicates that the solution is acidic.
1:52 If we add baking soda, the solution takes on a blue color. And what about household detergent? Wow!
2:15 The juice has turned green. Green means the solution is an alkali. If you like you can try out all sorts of other substances,
2:27 but please always ask a grown-up first to see which acids or cleaning products you’re allowed to use.
2:34 The chopped cabbage can now be cooked and eaten. And if you add some sour apples, then you guessed it! It will be bright red.
2:48 Bon appetit, and have fun experimenting!