Find the typical de-Broglie wavelength associated with a He atom in helium gas at room temperatuare `(27^@C)` and 1 atm pressure and compare it with the mean separation between two atoms under these conditions.

Obtain the de-Broglie wavelength associated with thermal neutrons at room temperature (27^@C) . Hence explain why a fast neutron beam needs to be thermalized with the environment before it can be used for neutron diffraction experiments.

Compute the typical de-Broglie wavelength of an electron in a metal at 27^@C and compare it with the mean separation between two electrons in a metal which is given to be about 2xx10^-10m .

Find de-Broglie wavelength associated with a proton of energy 2 MeV. Given, mass of proton is 1.67 xx 10^(-27) kg .

Assume that the de Broglie wave associated with an electron can from a standing wave between the atom arrange in a one dimensional array with nodes at each of the atomic sites. It is found that one such standing wave if the distance d between the atoms of the array is 2 A^0 A similar standing wave is again formed if d is increased to 2.5overset @A . Find the energy of the electrons in electron volts and the least value of d for which the standing wave type described above can from .

Find de-Broglie wavelength associated with an electrons moving with velocity 0.6 C. Given, rest mass of electron = 9.1 xx 10^-31 kg , h=6.63 xx 10^-34 Js .

Calculate volume occupied by two moles of gas at 27^@C and under a pressure of 1 atmosphere.

A heating coil is immersed in a 100 g sample of H_(2)O (l) at a 1 atm and 100^(@) C in a closed vessel. In this heating process , 60% of the liquid is converted to the gaseous form at constant pressure of 1 atm . The densities of liquid and gas under these conditions are 1000 kg//m^(3) and 0.60 kg//m^(3) respectively . Magnitude of the work done forthe process is : (Take : 1L-atm= 100J)

1 mole of a diatomic gas present in 10 L vessel at certain temperature exert a pressure of 0.96 atm. Under similar conditions an ideal gas exerted 1.0 atm pressure. If volume of gas molecule is negligible, then find the value of van der Waals' constant ''a'' (in atm L^(2)//mol^(2) ).

In the HC1 molecule, the separation between the nuclei of the two atoms is about 1.27 overset@A ( 1 overset@A = 10^-10 m ). Find the approximate location of the CM of the molecule, given that a chlorine atom is about 35.5 times as massive as a hydrogen atom and nearly all the mass of an atom is concentrated in its nucleus.