1. In the simple cubic unit cell, the centers of identical particles define the of a cube. The particles do touch along the cube's but do not touch along the cube's or through the center. There is/are particle per unit cell and the coordination number is . 2. In the body-centered cubic unit cell, the centers of identical particles define the of the cube plus particle at the of . The particles do not touch along the cube's or faces but do touch along the cube's . There is/are particles per unit cell and the coordination number is .
3. In the face-centered cubic cell, the centers of identical particles define the of the cube plus particle in the of . The particles on the do not touch each other but do touch those on the . There is/are particles per unit cell and the coordination number is .

please see below for answers in the spaces given.

Explanation:

There are three types of cubic-unit cells of a cubic systemwhich include Simple cubic unit cell, body-centered cubic unit cell and face-centered cubic-unit cell and Thier characteristics are completed below.

1) In the simple cubic unit cell, the centers of eight identical particles define the corners___ of a cube. The particles do touch along the cube's edges but do not touch along the cube's diagonal or through the center. There is/are one particle per unit cell and the coordination number is

__six .

2. In the body-centered cubic unit cell, the centers of eight identical particles define the corners of the cube plus one particle at the center of the cube . The particles do not touch along the cube's edges or faces but do touch along the cube's diagonal . There is/are two particles per unit cell and the coordination number is eight .

3. In the face-centered cubic cell, the centers of eight identical particles define the corner of the cube plus one particle in the center of each face . The particles on the corners do not touch each other but do touch those on the faces . There is/are four___ particles per unit cell and the coordination number is twelve .

i think it's letter a.

yes the answer is total mass in unchanged   : )