The smallest group of particles in a crystal that retains the shape of the crystal is called the
a. cube
b. unit cell
c. cage
d. crystal lattice

The correct answer is B.unit cell

Explanation:

An unit cell is an arrangement of particles (atoms, ions or molecules) in a crystal structure. The repetition of the unit cell reproduces the complete crystalline structure of the solid. Depending on how are located the particles, there are different unit cells, for exaple: simple cubic, body-centered cubic, face-centered cubic.

b) mutualism

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