The value of Rydberg constant $(R_H)$ is $2.18 \times 10^{-18} \mathrm{~J}$. The velocity of electron having mass $9.1 \times 10^{-31} \mathrm{~kg}$ in Bohr's first orbit of hydrogen atom = ________ $\times 10^5 \mathrm{~ms}^{-1}$ (nearest integer).
Answer (integer)
22
Solution
<p>$$\begin{aligned}
& \text { K.E. }=R_H \cdot \frac{z^2}{n^2}=\frac{1}{2} m v^2 \\
& v^2=\frac{2 \times 2.18 \times 10^{-18}}{9.1 \times 10^{-31}} \times \frac{1}{1}=0.479 \times 10^{13} \\
& v=21.88 \times 10^5 \mathrm{~m} / \mathrm{s}
\end{aligned}$$</p>
About this question
Subject: Chemistry · Chapter: Atomic Structure · Topic: Bohr's Model
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