What is the term that defines the smallest piece of a crystal that shows the shape of that type of crystal?

The correct answer to this open question is the following.

The term that defines the smallest piece of a crystal that shows the shape of that type of crystal is "unit cell."

In the atomic world, the smallest portion of a crystal lattice is a unite cell. A unit cell shows the 3D or three-dimensional pattern of the crystal. So this unite cell can repeat itself to form the crystal lattice. There are cubic cells, monoclinic cells, tetragonal cells, orthorhombic, cells, and rhombohedral cells.

If you add soap or detergent in water, the surface tension of water changes, the molecular bond of water becomes weaker. So, when light hits a plain water, it could either be reflected, or the water gets heated and evaporates, and then forms into gas.

Explanation:

Something like this?