Electromagnetic radiation of wavelength 242 nm is just sufficient to ionise the sodium atom. Calculate the ionisation energy of sodium in kJ mol-1.





Q.10:- Electromagnetic radiation of wavelength 242 nm is just sufficient to ionise the sodium atom. Calculate the ionisation energy of sodium in kJ mol-1.

 

 

Answer:-
E = Nhν = Nhc/λ = (6.022×1023 mol-1)×(6.626×10-34 Js×3.0×10ms-1)/242×10-9 m
   = 4.945×10Jmol-1 = 494.5 kJmol-1