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Grade 11Physical Chemistry

Iodine Molecue dissociates into atoms after absorbing light of 4500 A. If oone quantum of radiation is absorbed by each molecule, calculate K.E. of iodine atoms.

Profile image of Vishrant Vasavada
16 Years agoGrade 11
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1 Answer

Profile image of deeksha sharma
15 Years ago

WAVELTH=4500*10-10 m

energy=hc/wavelength=6.62*10-34 *3*108 /4500*10-10 =4.4*10-19 J

half of this energy goes to each atom i.e. 2.2*10-19 J

bond energy of iodine= 240kj/mol = 3.9*10-19 J/atom

for one atom=1.95*10-19 J

ke of iodine atoms= (2.2-1.95)*10-19 J =0.25*10-19 J=2.5*10-20 J