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Atoms & Nuclei

JEE Main level, single correct, medium

74 of 239

Question 74 of 239

Radiation coming from transitions $n=2$ to $n=1$ of hydrogen atoms fall on ${He}^{+}$ ions in $n=1$ and $n=2$ states. The possible transition of helium ions as they absorb energy from the radiation is:

Show answer and solution

Answer: (B) $n=2⟶n=4$

E=13.6\left(\dfrac{1}{{1}^{1}}-\dfrac{1}{{2}^{2}}\right)eV...(1)

For Helium:

E=13.6{\left(2\right)}^{2}\left(\dfrac{1}{{n}_{1}^{2}}-\dfrac{1}{{n}_{2}^{2}}\right)eV...(2)

From equation

(1)

and

(2)

13.6\left(\dfrac{3}{4}\right)=13.6\left(4\right)\left(\dfrac{1}{{n}_{1}^{2}}-\dfrac{1}{{n}_{2}^{2}}\right)

\dfrac{1}{{n}_{1}^{2}}-\dfrac{1}{{n}_{2}^{2}}=\dfrac{3}{16}

From option,

{n}_{1}=2

and

{n}_{2}=4

are satisfying the equation.

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Radiation coming from transitions n=2n=2n=2 to n=1n=1n=1 of hydrogen atoms fall on He+{He}^{+}He+ ions in n=1n=1n=1 and n=2n=2n=2 states. The possible transition of helium ions as they absorb energy from the radiation is:

JEE Main question paper PDF

More Physics practice

Radiation coming from transitions $n=2$ to $n=1$ of hydrogen atoms fall on ${He}^{+}$ ions in $n=1$ and $n=2$ states. The possible transition of helium ions as they absorb energy from the radiation is: