Easy MCQ +4 / -1 PYQ · JEE Mains 2020

The de Broglie wavelength of an electron in the 4th Bohr orbit is :

  1. A 2$\pi$a<sub>0</sub>
  2. B 6$\pi$a<sub>0</sub>
  3. C 8$\pi$a<sub>0</sub> Correct answer
  4. D 4$\pi$a<sub>0</sub>

Solution

According to Bohr’s model <br><br>${r_n} = {{{n^2}} \over Z} \times {a_0}$ <br><br>Also 2$\pi$${r_n}$ = n$\lambda$ <br><br>$\Rightarrow$ 2$\pi$${{{n^2}} \over Z} \times {a_0}$ = n$\lambda$ <br><br>$\Rightarrow$ $\lambda$ = $2\pi \times {n \over Z} \times {a_0}$ <br><br>For n = 4 and Z = 1 <br><br>$\Rightarrow$ $\lambda$ = 8$\pi$${a_0}$

About this question

Subject: Chemistry · Chapter: Atomic Structure · Topic: Bohr's Model

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