NEET Chemistry Structure of Atom / परमाणु संरचना NEET PYQ-Structure of Atom

  • question_answer
    Bohr radius for the hydrogen atom \[(n=1)\] is approximately \[0.530\,\overset{o}{\mathop{A}}\,\]. The radius for the first excited state \[(n=2)\] orbit is (in \[\overset{o}{\mathop{A}}\,\]):                             [AIPMT 1998]

    A)  0.13 

    B)                   1.06                

    C) 4.77  

    D)  2.12

    Correct Answer: D

    Solution :

    \[r\propto \,n_{1}^{2}\,{{Z}^{2}}\]
                where    n = number of orbit
                            Z = Atomic number
                \[\because \]       \[{{r}_{1}}\propto n_{1}^{2}\]
                            \[{{r}_{2}}\propto \,n_{2}^{2}\,(Z=1\,for\,H-atom)\]
                So,       \[\frac{{{r}_{1}}}{{{r}_{2}}}=\frac{n_{1}^{2}}{n_{2}^{2}}\]
                            \[\frac{0.530}{{{r}_{2}}}=\frac{{{1}^{2}}}{{{2}^{2}}}\]
                \[\therefore \]      \[{{r}_{2}}=0.530\times 4=2.120\,{\AA}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner