Question

The kinetic energy of electron in H-atom is 1.5 evolt/atom what is the velocity of electron ​

Answer 1

It has given that, kinetic energy of an electron in H - atom is 1.5 eV/atom.

To find : The velocity of the electron...

solution : A/C to Bohr's atomic theory,

kinetic energy of an electron in an orbit of H - atom is given by, E = 13.6/n² eV/atom.

but given, E = 1.5 eV/atom

so, 1.5 eV/atom = 13.6/n² eV/atom

⇒1.5/13.6 = 1/n²

⇒n² = 13.6/1.5 ≈ 9

⇒n = 3

Now using formula of velocity of electron in an orbital,

i.e., v = 2.18 × 10⁶/n , putting n = 3

v = 2.18 × 10⁶/3 = 0.726 × 10⁶ m/s

= 7.26 × 10⁵ m/s

Therefore the velocity of the electron is 7.26 × 10⁵ m/s.