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org19 Reducing the surface tension of water, disadvantages of soap

Left and Photo 1: Soap reduces the surface tension or water: 0.1 ml water  (left) gave 17 round micro drops on a plastic surface.  28 flat micro drops  (Photo 2) were obtained from 0.1 ml soap water.
Explanation  The reduced surface tension of water resulted in 1. its finer distribution due to lower cohesion and 2. its a bigger contact area between each water drop and the water repellent plastic surface (plastic was wetted).
Photos 3 and 4: A protein solution acts like soap: Shake 1 ml Becel plant oil and 3 ml protein solution. For control mix 1 ml 1 ml Becel plant oil and 3 ml water.
Observations:  Oil separates from water immediately after the end of shaking. Oil and protein solution formed a stable cloudy mixture. Explanation: Lecithin, a substance in the protein solution, acts like soap: Both are somewhat that is compatible with both the water and the oil. Both have a similar molecular structure with long hydrocarbon "tails" (compatible to the hydrocarbon tails of oil molecules) and ionic "heads" (compatible to water molecules).
Right: Some drops of soap solution from the previous experiment are mixed with hard and with soft water. Observations (click here): After shaking of soft water (from bottle 3) with soap solution foam and a transparent solution reamain. Hard water (lime water) from the left bottle shaked with soap solution give no stable foam and white flakes appear.
Explanation: In hard water dissolved soap is transformed into non-soluble lime soap. This cannot be properly removed from the textiles.