Question

The ratio of 2nd orbits of hydrogen atom is:

• A. $2:4:6$
• B. $1:4:9$
• C. $1:4:6$
• D. $1:2:3$

Answer 1

The correct option is B $1:4:9$

The ratio of 2nd, 4th and 6th orbits of hydrogen atom is $1:4:9$.
The radius of hydrogen atom is directly proportional to the square of the principal quantum number.
$r_2:r_4:r_6=2^2:4^2:6^2=4:16:36=1:4:9$