Question

In the case of nanostructures, the ratio of number of atoms on the surface to the number of atoms in the interior is ........

• A. exactly zero because the total tends to infinity
• B. may be of the order of unity
• C. always 0.5
• D. tends to infinity because the surface energy tends to infinity

Hint:

For nanostructures, surface atoms play a crucial role in determining material properties. As the size decreases, the ratio of surface atoms to interior atoms increases.

Answer 1

The Correct Option is B

In nanostructures, the ratio of the number of atoms on the surface to the number of atoms in the interior is significant. As the size of the nanostructure decreases, the surface area increases relative to the volume. This leads to an increased number of surface atoms compared to the interior atoms. For small nanostructures, this ratio may be of the order of unity, meaning the number of surface atoms is comparable to the number of interior atoms.
However, for larger materials, this ratio decreases as the interior atoms outnumber the surface atoms. As the material approaches the macroscopic scale, the ratio tends to zero because the total number of atoms tends to infinity, and the surface area becomes a smaller fraction of the whole.
Therefore, the correct answer is: may be of the order of unity.