Question

the electromagnetic spectrum and electronic transitions
energy of light
the 240. nm wavelength, in the ultraviolet portion of the spectrum, has a frequency of
1.25 x 10¹⁵ s⁻¹.
calculate the energy of the photon in joules.
useful equations and constants:
$c = \lambda\
u$
$e = h\
u$
$c = 3.0 \times 10^8$ m/s
$h = 6.626 \times 10^{-34}$ j·s
avogadros number = $6.02 \times 10^{23}$ mol⁻¹
what is the energy required to break the oxygen double bond?
3.80 x 10²³ j
8.28 x 10⁻¹⁹ j
5.30 x 10⁻⁴⁹ j
1.88 x 10¹⁸ j

Explanation:

Step1: Use photon energy formula

$E = h
u$

Step2: Substitute given values

$E = 6.626 \times 10^{-34}\ \text{J·s} \times 1.25 \times 10^{15}\ \text{s}^{-1}$

Step3: Calculate the product

$E = 6.626 \times 1.25 \times 10^{-34+15} = 8.2825 \times 10^{-19}\ \text{J}$

Answer:

B. 8.28 x 10⁻¹⁹ J