Atomic Structure Question 191
Question: The energy required to break 1 mol of $ Cl-Cl $ bonds in $ Cl_2 $ is 242 kJ/mol. The longest wavelength of light capable of breaking a single $ Cl-Cl $ bond is
Options:
A) 594 nm
B) 640 nm
C) 700 nm
D) 494 nm
Show Answer
Answer:
Correct Answer: D
Solution:
- Energy required for 1 $ Cl_2 $ molecule $ =\frac{242\times 10^{3}}{N_{A}}J $
$ E=\frac{hc}{\lambda } $ or $ \lambda =\frac{hc}{E} $
$ =\frac{6.626\times {10^{-34}}\times 3\times 10^{8}\times 6.02\times 10^{23}}{242\times 10^{3}} $
$ =494\times {10^{-9}}m=494nm $