the heat of atomization of methane and ethane are 360 KJ/mol and 620 KJ/mol , respectively . The longest Wavelength of light capable of breaking . The c-c bond is :
(Avogadro number`=6.02xx10^(23),h=6.62xx10^(-34)Js)`

Options

A. `2.48xx10^(4)m`
B. `1.49xx10^(3)m`
C. `2.48xx10^(3)m`
D. `1.49xx10^(4)nm`

Answer

B

Explanation

In `CH_(4), 4xxBE_((C-H))=360` kJ/mol
`:.BE_((C-H))=90` kJ/mol
In `C_(2)H_(6),BE_((C-C))+6xxBE_((C-H))=620` kJ/mol
`:.BE_((C-C))=80` kJ/mol
`:.BE_((C-C))=(80xx10^(3))/(60.23xx10^(23))` J/molecule
Now `E=(hc)/(lamda)`
`:.lamda=(60626xx10^(-34)xx3xx10^(8)xx6.023xx10^(23))/(80xx10^(3))`
`:.lamda=1.49xx10^(3)` nm