Final answer:
In interstellar space, the number of dust particles is typically much fewer than the number of gas particles. These particles are distributed in a patchy and irregular way.
Step-by-step explanation:
In interstellar space, the number of dust particles is typically much fewer than the number of gas particles. If all the interstellar gas were spread out smoothly, there would be about one atom of gas per cm³, while a km³ of space would contain only a few hundred to a few thousand tiny dust grains. However, these numbers are just averages, as the distribution of gas and dust in space is patchy and irregular.