(a) Draw a picture that represents a crystalline solid at the atomic level. (b) Now draw a picture that represents an amorphous solid at the atomic level.

To draw a crystalline solid at the atomic level: 1. Draw a simple unit cell. A unit cell is a repeating structure of atoms (represented by circles or spheres) in a regular pattern. A square lattice is a straightforward example. 2. Draw four circles or spheres at the corners of this square. 3. Extend the unit cell both vertically and horizontally by repeating this pattern. 4. Complete the crystalline solid by drawing more rows and columns of unit cells to demonstrate the organized and repeating structure.

To draw an amorphous solid at the atomic level: 1. Draw multiple circles or spheres representing atoms, but without any clear repeating pattern or organization. Make sure to keep the distribution of atoms irregular. 2. Fill the drawing with more atoms, maintaining the randomness in their arrangement. 3. As opposed to the crystalline solid, no clear unit cells or repeating structures should be visible in the amorphous solid due to their disordered arrangement. Once you have completed both drawings, it should be easy to see the difference between the two types of solids at the atomic level - the crystalline solid has a well-organized and repeating structure, while the amorphous solid has a random and disordered atom arrangement.