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W3 Soap reduces the surface tension of water

Material
Tray, insulin syringe 1 ml (Take only syringes from a pharmacy!), blunted hypodermic needle (0.45 x 25 mm), 2 high ampoules (5 ml), toilette paper, plastic surface, detergent, tapwater.

Experiment: *  Left: Totally fill a Liquemin bottle with water. Turn it upwards down.
* Photo 2: Repeat the same experiment with water, which was mixed with a drop of liquid soap.
* Photo 3: Suck 1 ml of water into a syringe with a thin blunted needle.
* Totally remove air bubbles and adjust exactly to 1 milliliter (ml).
* Photo 4: Distribute 0.1 ml water on a plastic surface as micro drops.
*  Right: Repeat the former experiment, replacing the water by soap water.
Observations and explanations: Soap causes a reduction of  surface tension in water:
1. Water easily flows out of the small bottle.   2. Water distributes into smaller drops (28 instead of 17 /  0.1 ml).
3. Each dropf touches a greater area of the plastic surface.