Question

40. Taking the Bohr radius as al = 53 pm, the radius of Lit+ ion in its ground state, on the basis of Bohr's
model, will be about
(A) 53 pm
(B) 27 pm
(C) 18 pm
(D) 13 pm​

Answer 1

Answer:

$\red{\textbf{Answer :- (c) 18pm}}$

Explanation:

$\red{\textbf{Given :-}}$

$\textsf{According to Bohr's model of atom, }$

$\textsf{of an atom in its ground state is }$

$\Large r = \LARGE \frac{r_{o}}{z}$

$\textsf{where r is Bohr's radius,}$

$\textsf{and Z is atomic number.}$

$r _{o} = 53pm$

$\textsf{ atomic number of Lithium atom is 3}$

$\Large r = \LARGE\frac{53}{3}$

$= 17.67 \: pm$

$\textsf{=18pm verifies option (c).}$

$\red{\textbf{More information :-}}$

• $\textsf{The Bohr radius is a physical constant,}$

• $symbol = a_{o} \: or \: \: r _{bohr}$
• $SI \: unit \: = 5.29 \times 1 {0}^{ - 11} m$
• $Natural \: unit \: = 3.27 \times 10^{24} l_{p}$