Question

It takes 155. kJ/mol to break a fluorine-fluorine single bond. Calculate the maximum wavelength of light for which a fluorine-fluorine single bond could be broken by absorbing a single photon. Be sure your answer has the correct number of significant digits.

Answer 1

1.3*10^-30m

Step-by-step explanation:

The energy of the bond= energy of the photon.

E=hf f=E/h= 155*10^3/6.6*10^-34= 23.5*10^37 Hz

But V=wavelength* frequency

Wavelength= 3*10^8/23.5*10^37 = 1.3*10^-30 m

Note, speed of a photon of light= 3*10^8 ms-1

Answer 2

772 nanometers.

Step-by-step explanation:

The maximum wavelength of light corresponds to minimum energy required to break one mole of flourine-flourine single bond which is 155 kJ.

Energy required to break one F-F bond is
`(155)/(6.023 * 10^(23) )` kJ.

Energy of photon is given by:

E=\frac{nhc}{\lambda}[/tex]

where

n = number of photons h=
`6.626 * 10^(-34)`Js and
`\lambda`=wavelength of photon and c=
`3 * 10^(8)`
`(m)/(s)`

In this question E=
`(155 * 10^(3))/(6.023 * 10^(23) )`

and n=1

Substituting appropriate values in the above equation, we get:

`\lambda=0.77242* 10^(-6)` metres

=772.42 nanometers

=772 nanometers as value given in the question has 3 significant digits.