The radius of the 2nd orbit of Li²⁺ is x. The expected radius of the 3rd orbit of Be³⁺ is (a) 9/4 × x (b) 4/9 × x (c) 27/16 × x (d) 16/27 × x

Correct answer :(C)orbit

The Bohr radius   is defined as the distance between the nucleus and the outermost electron in hydrogen atom in its ground state. It represents the distance between the nucleus and electron in hydrogen’s ground state (n=1), It approximately equal to 0.529 Å.

Information about orbit :

orbit represents a fixed circular path around the atomic nucleus where electrons revolve without losing energy, as proposed in Niels Bohr’s 1913 model of the hydrogen atom. Orbit has the following specific characters:

1. Orbit is a circular path in which electron is  revolving around the nucleus.

2. It represents 2-D motion of an electron

3.  Maximum number of electrons can be accommodated in an orbit is  2n².

4. Shape of the orbit is circular.

5. position  and velocity of an electron can be found precisely at any instant.

According to Bohr’s atomic model,  it has been possible to estimate the value of the radius of first orbit of hydrogen atom( 0.529 Å).