The energy required to break one mole of hydrogen-hydrogen bonds in `H_(2)` is 436 kJ. What is the longest wavelength of light required to break a single hydrogen-hydrogen bond-

Options

A. 68.5 nm
B. 137 nm
C. 274 nm
D. 548 nm

Answer

C

Explanation

The energy required to break a H-H bond
`=(436xx10^(3))/(6.022xx10^(23))J`
Therefore, from the equation, `E=(hc)/(lamda)`
we get, `(hc)/(lamda)=(436xx10^(3))/(6.022xx10^(23)`
`therefore lamda=(6.022xx10^(23))/(436xx10^(3))xxhc`
`=(6.022xx10^(23))/(436xx10^(3))xx6.626xx10^(-34)xx3xx10^(8)`
`=2.74xx10^(-7)m=274nm`