The frequency of this line of vanadium is 9.38 x10 ^14 Hz.
Emission spectrum shows how the electron of an atom goes or moves from a higher to a lower energy level.
Now The energy of a photon is given by
E = hc/λ
where
h = Plank's constant = 6.626 x 10⁻³⁴ J s
c = speed of light= 3 x 10⁸ m/s
λ = wavelength = 318.5 x 10⁻⁹ m
Solving
E = (6.626 x 10⁻³⁴ J s x 3 x 10⁸ m/s) / 318.5 x 10⁻⁹ m
E =6.2166 x10 ^-19 J
Also, we know that energy is related to frequency by the equation
E =hf
Where;
h = Planks's constant
f = frequency of photon
Making frequency subject of the formulae
f = E/h
f =6.2166 x10 ^-19 J/ 6.626 x 10⁻³⁴ J s
f = 9.38 x10 ^14 Hz
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