Write the value of n, l and m for the electron with the highest energy in sodium atom (Z =11).

With the help of ground state electronic configuration of element Cr(Z= 24), deduce the possible values of four quantum numbers for the 19th electron of Cr.

A stream of electrons from a heated filament was passed between two charged plates kept at a potential difference V esu. If e and m are charge and mass of an electron, respectively, then the value of h/λ (where λ is wavelength associated with electron wave) is given by:

• 2meV

• 
• 
• 

258.

Which of the following is the energy of a possible excited state of hydrogen?

• +13.6 eV

• -6.8 eV

• -3.4 eV

• -3.4 eV

The correct set of four quantum numbers for the valence electrons fo rubidium atom (Z = 37) is

• 5,0,0, +1/2

• 5,1,0,6+1/2

• 5,1,1,+1/2

• 5,1,1,+1/2

Energy of an electron is given by
E =- 2.178 x 10^-18 J 
Wavelength of light required to excite an electron in a hydrogen atom from level n =1 to n=2 will be (h=6.62 x 10³⁴ Js and c = 3.0 x 10⁸ ms^-1) 

• 1.214 x 10^-7 m

• 2.816 x 10^-7 m

• 6.500 x 10^-7 m

• 6.500 x 10^-7 m