JEE Mains · Chemistry · STD 11 - 2. structure of atom
Assume that the radius of the first Bohr orbit of hydrogen atom is \(0.6 \mathring A\). The radius of the third Bohr orbit of \(He ^{+}\)is \(..................\) picometer. (Nearest Integer)
- A \(170\)
- B \(180\)
- C \(270\)
- D \(250\)
Answer & Solution
Correct Answer
(C) \(270\)
Step-by-step Solution
Detailed explanation
\(r \propto \frac{ n ^2}{ Z }\) \(r _{ He ^{+}} = r _{ H } \times \frac{ n ^2}{ Z }\) \(r _{ He ^{+}} =0.6 \times \frac{(3)^2}{2}\) \(=2.7 \mathring A\) \(r _{ He ^{+}} =270\,pm\)
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