Atoms & Nuclei

JEE Main level, numerical answer, medium

50 of 239

Question 50 of 239

The radius of fifth orbit of Li++{Li}^{++} is_______\times {10}^{-12}m. Take: radius of hydrogen atom=0.51A∘=0.51A^{^{\circ}}

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Answer: 425

The formula to calculate the radius of Lithium-ion is given by
RLi=RH×n2Z...(1){R}_{Li}={R}_{H}\times \dfrac{{n}^{2}}{Z}...(1)
Substitute the values of the known parameters into equation (1) to calculate the required radius of the ion.
RLi=0.51×253×10−10m=425×10−12m\begin{matrix}{R}_{Li} & = & \dfrac{0.51\times 25}{3}\times {10}^{-10}m \\ & = & 425\times {10}^{-12}m\end{matrix}

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