Question

In hydrogen spectrum, the third line from the red end corresponds to which one of the following inter-orbit jumps of the electrons from Bohr orbit of hydrogen?

• A. $4\to 1$
• B. $2\to 5$
• C. $3\to 2$
• D. $5\to 2$

Answer 1

Answer: (D)

$5\to 2$

$Explanation:$

The Hydrogen spectrum forms the red end it means that it is visible to the eyes. The visible region lies in the $Balmerseries$ where $n_1=2$.

$\therefore n_1=2$

The electron has minimum energy in the first orbit and its energy increases as $n$ increases. Here $n$ represents the number of orbits, The third line from the red end corresponds to the yellow region i.e.,$5$.

$\therefore n_2=5$

Thus the electron jump from $5\to 2$

$Hencethecorrectanswerisoption\left(D\right).$