The radius of the second Bohr orbit for hydrogen atom is (Planck's constant, ( h ) = 6 .6262 × 10 − 34 Js ; mass of electron = 9 .1091 × 10 - 31 kg ; charge of electron = 1 .60210 × 10 - 19 C ; permittivity of vacuum, ( ∈ 0 ) = 8 .854185 × 10 - 12 kg - 1 m - 3 A 2 )

Step-by-step solution

Radius of the Bohr's orbit is calculated by the following formula r n = 0 .529 × n 2 z Å Radius is directly proportional to square of n th orbit and inversely proportional to atomic number. This formula works for single electron species here r n = radius of the nth orbit Z = 1   and   n = orbit or shell number r 2 = 0 .529 × 2 2 1  Å = 2 .12  Å