I just read this quote on wiki;

"Materials reduced to the nanoscale can show different properties compared to what they exhibit on a macroscale, enabling unique applications. For instance, opaque substances can become transparent (copper); stable materials can turn combustible (aluminium); insoluble materials may become soluble (gold). A material such as gold, which is chemically inert at normal scales, can serve as a potent chemical catalyst at nanoscales. Much of the fascination with nanotechnology stems from these quantum and surface phenomena that matter exhibits at the nanoscale.^[26]

^{https://en.wikipedia.org/wiki/Nanotechnology}

How is that possible?

For example why would Gold be soluble at the nano scale and yet not on the macroscale? 

 

Edited June 19, 20196 yr by thethinkertank

One effect is the available surface area, in proportion to the number of atoms