JEE Mains · Chemistry · STD 11 - 2. structure of atom
Radius of the first excited state of Helium ion is given as : \(\mathrm{a}_0 \rightarrow\) radius of first stationary state of hydrogen atom.
- A \(\mathrm{r}=4 \mathrm{a}_0\)
- B \(\mathrm{r}=2 \mathrm{a}_0\)
- C \(r=\frac{a_0}{2}\)
- D \(r=\frac{a_0}{4}\)
Answer & Solution
Correct Answer
(B) \(\mathrm{r}=2 \mathrm{a}_0\)
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & \mathrm{r}=\mathrm{a}_0\left(\frac{\mathrm{n}^2}{\mathrm{z}}\right) \\ & \mathrm{r}=\frac{\mathrm{a}_0(2)^2}{(2)} \\ & \mathrm{r}=2 \mathrm{a}_0\end{aligned}\)
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