Among the following , which orbital in `Be^(3+)` has same energy as that of electron in `He^+` in ground state and also has 2 angular nodes ?

What is the energy of the electron in He^(+) in ground state?

Among the following which orbital has least energy?

What is the energy of the electron in He+ ion in the ground state ?

What is the energy of the electron in He^(Theta) in the ground state ?

Which orbit of Be^(3+) has almost same radius as that of the ground state of H-atom?

Which set has the same number of unpaired electrons in their ground state?

The electron revolving in the n-th orbit of Be^(3+) ion has the same speed as that of the electron in the ground state of hydrogen atom. Find the value of n.