Photochemical dissociation produces a normal oxygen atom and a oxygen atom 2.5 eV more energetic than normal one. Also the average bond energy of O2 into normal oxygen is 498 kJ mol-1 . Determine the longest wavelength required for photochemical decomposition of O2 .

Question

Photochemical dissociation produces a normal oxygen atom and a oxygen atom 2.5 eV more energetic than normal one. Also the average bond energy of O2 into normal oxygen is 498 kJ mol-1 . Determine the longest wavelength required for photochemical decomposition of O2 . (A) 126 nm (B) 175 nm (C) 190 nm (D) 205 nm

Tardigrade Admin · Accepted Answer

BE of O2 per molecule =(498× 103/6.023× 1023)J =826× 10-19J Energy required for photochemical decom-position of one molecule of O2=826× 10-19J+2.5× 1.6× 10-19J =1.22× 10-18J λ =(hc/E)=(6.625× 10-34× 3× 108/1.22× 10-18)=126 nm

Q. Photochemical dissociation produces a normal oxygen atom and a oxygen atom 2.5 eV more energetic than normal one. Also the average bond energy of O2​ into normal oxygen is 498 kJ mol−1 . Determine the longest wavelength required for photochemical decomposition of O2​ .

126 nm

175 nm

190 nm

205 nm

BE of O2​ per molecule =6.023×1023498×103​J =826×10−19J Energy required for photochemical decom-position of one molecule of O2​=826×10−19J+2.5×1.6×10−19J =1.22×10−18J λ=Ehc​=1.22×10−186.625×10−34×3×108​=126nm

Q. Photochemical dissociation produces a normal oxygen atom and a oxygen atom 2.5 eV more energetic than normal one. Also the average bond energy of $O_{2}$ into normal oxygen is 498 kJ $m o l^{- 1}$ . Determine the longest wavelength required for photochemical decomposition of $O_{2}$ .