1.what is the volume of NaCl in cubic cm and cubic nm if the Length is 0.563 nm?
2. the density of NaCl is 2.17 g/cm. What is the Mass?
3. Each repeating unit is composed of 4 NaCl molecules. What is the Mass of 1 NaCl molecule?
1. These are just unit changes? What is the problem you are having?
2. mass = volume x density. Substitute and solve for mass.
3. I'm confused; you used molecules in two different ways.