The circumference of the second orbit of an atom or ion having single electron, is 4 nm. The de-Brog — Atomic Structure Chemistry Question

💡 Solution & Explanation

According to Bohr's quantization rule, the circumference of an orbit is an integral multiple of the electron's de-Broglie wavelength: $2\pi r = n\lambda$. For the second orbit ($n=2$), the circumference is $2\lambda$. Given circumference = 4 nm, we have $2\lambda = 4 \text{ nm} \implies \lambda = 2$ nm. Therefore, correct answer is 2.