Identify the process from following such that volume of system remains constant.

Identify the instrument used to find crystal structure from following :

In a solution, mole fraction of solute is 0.2 , when lowering in vapour pressure is 10 mm Hg . To get lowering of vapour pressure of 20 mm Hg , mole fraction of solute in solution is

Which among the following is an example of one dimensional nanostructure?