The radius of the innermost electron orbit of a hydrogen atom is `5.3 xx 10^-11m . What are the radii the n=2 and n=3 orbits?

Bohr combined classical and early quantum concept and gave his theory in the form of three postulates. The radius of innermost electron orbit of hydro gen atom is 5.3 * 10^-11m. What are the radii of n = 2 and n = 3 orbits?

The energy of electron in 3rd orbit of hydrogen atom is:

i. The energy associated with the first-orbit in the hydrogen atom is -2.18 xx 10^(-18)J atom^(-1) . What is the energy associated with the fifth orbit?

The radius of the first Bohr orbit of hydrogen is 0.529A^(@) . The radius of the 3^(rd) orbit of He^(+) will be