The ionization energy of He+ is 19.6 10^-18 J atom^-1. The energy of the first stationary state of Li+2 will be :

Show that the wavelength of a 150 g rubber ball moving with a velocity 50 m sec^-1 is short enough to be observed ..

If an electron is present in n = 6 level. How many spectral lines would be observed in case of H atom ...

What arethe differance between "Nodal surface" and "Nodal plane" ?

Nodal Surface : The place find in between two "s" orbitals where the value of electron density is equal to zero called Nodal surface. 

Nodal Plane : The plane for "p" and "d" orbitals where the value of electron density is equal to zero called Nodal Plane. 

Speed of helium atom at 300K is 2.40 x10^2 meter per sec. What is its wave length. (mass number of helium is 4)..