Electromagnetic radiationof wavelength242nm isjustsufficientto ionise thesodiumatom .Calculatethe ionisation energyofsodiumin Kj mol^(-1)

Electromagnetic radiationof wavelength242nm isjustsufficientto ionise

1.	Electromagnetic radiationof wavelength242nm isjustsufficientto ionise thesodiumatom .Calculatethe ionisation energyofsodiumin Kj mol^(-1)
Answer» Solution :where `lambda= 242nm =242 xx 10^(9) m`wavelengthper photon`E= (hc )/(lambda ) ` permoleE = `(N_(A) hc )/(lambda )` `n=6.626 xx 10^(34)Js` `c=3.0xx 10^(8) m` `N_(A)= 6.022xx 10^(23)` permole `=(6.022 xx 10^(23) mol^(1)xx 6.626 xx 10^(34)js xx3.0 xx 10^(8) MS^(-1)J)/( (242 xx 10^(9) m))` `=494.7 xx KJ mol^(-1)495kJ mol^(1)` Ionisationenthalpy=495kJ `mol^(1)`