Atoms Ques 45
45. What is the radius of iodine atom (At. no. 53, mass no. 126)
[1988]
(a) $2.5 \times 10^{-11} m$
(b) $2.5 \times 10^{-9} m$
(c) $7 \times 10^{-9} m$
(d) $7 \times 10^{-6} m$
Show Answer
Answer:
Correct Answer: 45.(a)
Solution:
- (a) 53 electrons in iodine atom are distributed as $2,8,18,18,7$
$ \begin{aligned} \therefore n & =5 \\ r_n & =(0.53 \times 10^{-10}) \frac{n^{2}}{Z} \\ & =\frac{0.53 \times 10^{-10} \times 5^{2}}{53}=2.5 \times 10^{-11} m \end{aligned} $