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An electron moves from an energy level of -8.6 eV to anot...

An electron moves from an energy level of -8.6 eV to another level of -3.5 eV. Determine the frequency of the absorbed radiation. [1 eV = 1.6 × 1019 J, h = 6.6 × 1034 Js]

A.

2.93×1015Hz

B.

3.59×1016Hz

C.

5.39×1015Hz

D.

1.24×1015Hz

Correct answer is D

h = 6.6×1034Js, 1eV =  1.6×1019J, E1 = - 8.6eV, E2 = - 3.5eV, f = ?

ΔE = hf 

f = \frac{ΔE}{h}

ΔE =  E_2 -  E_1 = - 3.5eV - (- 8.6eV) = 5.1eV

but 5.1eV = 5.1 X  1.6 \times 10^{-19} 8.16 \times 10^{-19}J

f =  \frac{8.16 \times 10^{-19}}{ 6.6 \times 10^{-34}}

Therefore, f =  1.24 \times 10^{15}Hz