A) 74
B) 75
C) 72
D) 73
Correct Answer: C
Solution :
[c] We use the formula, \[R={{R}_{0}}{{A}^{1/3}}\] This represents relation between atomic mass and radius of the nucleus. For berillium, \[{{R}_{1}}={{R}_{0}}{{(9)}^{1/3}}\] For germanium, \[{{R}_{2}}={{R}_{0}}{{A}^{1/3}}\] \[\frac{{{R}_{1}}}{{{R}_{2}}}=\frac{{{(9)}^{1/3}}}{{{(A)}^{1/3}}}\Rightarrow \frac{1}{2}=\frac{{{(9)}^{1/3}}}{{{(A)}^{1/3}}}\] \[\Rightarrow \,\,\,\,\,\frac{1}{8}=\frac{9}{A}\Rightarrow A=8\times 9=72.\]
You need to login to perform this action.
You will be redirected in
3 sec
