Respuesta :
The electron in a ground-state h atom absorbs a photon of wavelength 121.57 nm it moves second energy level.
First convert wave length to energy
E = hc/ 2
E = 6. 62 6 x [tex]10^{-34}[/tex] J.S X 3. 0 x [tex]10^{8[/tex]m/s ÷ 121. 5 7 x [tex]10^{-9}[/tex] m
E = 1. 6 x [tex]10^{-18}[/tex]
Now
ΔE = 2.18 * [tex]10^{-18}[/tex] J[1 - [tex]\frac{1}{nf^{2} }[/tex]]
[tex]\frac{1}{nf^{2} }[/tex] = 0.2 26
[tex]{nf^{2} }[/tex] = 4.4
nf = 2.09
it moves to the second energy level
Electrons may be found at specific intervals from an atom's nucleus known as energy levels, also referred to as electron shells. In an atom, the small, positively charged electrons that orbit the central positive nucleus are known as electrons. Energy levels resemble a staircase's steps in certain ways. You cannot stand between the steps but may stand on either one. Electrons operate similarly. They can occupy either an energy level or another, but not the region in between.
Learn more about energy level here:
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