What happens to soap and pepper in water?

Answer 1

ONLY PARTIALLY CORRECT: because of the surfice tension, the pepper is floating and when soap is applied the soap spreads rappidly so the soap accually pushes the pepper to the side

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This can't be the answer because it works the same whether you use liquid soap or powder -- which isn't "spreading rapidly". I used a single grain of Tide Laundry Detergent and saw the same effect but on a smaller scale. I dropped it in, and the grain was still visible while the pepper moved away.

It's surface tension, yes, but NOT "soap spreads rapidly" and NOT "pushes pepper to the side"". The surface tension is broken because of the form and function of the soap molecules in relation to the water molecules. The pepper remains floating where the surface tension remains strong.
This is because the soap breaks the surface tension of the water and the tension on the rest of the water pulls the floating pepper away from the soap.

Water molecules are very sticky. They have a strong attraction to other water molecules. In the center of a glass of water, the molecules are sticking to other water molecules in all directions.

The water molecules beside your finger suddenly stick to the soap molecules instead of each other. The other water molecules on the surface are still pulling and the water at the edges is still pulling, but the water in the center is not pulling back. The surface molecules and the pepper sat on the surface are all pulled quickly to the sides.
because of the tension
The actual science happens because the soap breaks the surface tension of the water, like popping a balloon. It is the water that moves, not the pepper that is floating on it.
The actual science happens because the soap breaks the surface tension of the water , like popping a ballon . It is the water that moves , not the the pepper that is floating on it .
Water molecules are very sticky. They have a strong attraction to other water molecules. In the center of a glass of water, the molecules are sticking to other water molecules in all directions.

The water molecules beside your finger suddenly stick to the soap molecules instead of each other. The other water molecules on the surface are still pulling and the water at the edges is still pulling, but the water in the center is not pulling back. The surface molecules and the pepper sat on the surface are all pulled quickly to the sides.
Because the detergent reduces the cohesiveness of the pepper and the pepper along the sides pulls the pepper towards the sides
This is my theory:

Like many detergents, soap pulls apart molecules. That is the whole point, to loosen dirt. So soap separates the pepper and the water. Detergents break up the water's surface tension, making the pepper separate.