Make a drawing, based on the kinetic-molecular theory and the ideas about atoms and molecules presented in this chapter, of the arrangement of particles in each of the cases listed here. For each case, draw 10 particles of each substance. It is acceptable for your diagram to be two dimensional. Represent each atom as a circle, and distinguish each different kind of atom by shading. 

(a). A homogeneous mixture of water vapor and helium gas (which consists of helium atoms)

(b). A heterogeneous mixture consisting of liquid water and solid aluminum; show a region of the sample that includes both substances.

(c). A sample of brass (which is a homogeneous solid mixture of copper and zinc)