In the hydrogen atom, the energy levels of orbitals are determined solely by the principal quantum number \( n \). The hydrogen atom does not have electron-electron repulsion, so the energy of orbitals with the same principal quantum number \( n \) (like 3s, 3p, and 3d) are degenerate, meaning they have the same energy.
- Option A: This is correct because in the hydrogen atom, orbitals with the same \( n \) (such as 3s, 3p, and 3d) have the same energy, as the energy depends only on the principal quantum number, not the type of orbital (s, p, or d).
- Option B: This is incorrect. While in multi-electron atoms, the 3s and 3p orbitals are lower in energy than the 3d orbital, in the case of the hydrogen atom, all the 3 orbitals (3s, 3p, and 3d) have the same energy.
- Option C: This is incorrect for the hydrogen atom. All the orbitals with the same principal quantum number have the same energy.
- Option D: This is incorrect for the hydrogen atom. The energy of the 3s orbital is not necessarily lower than the 3p orbital; both have the same energy in a hydrogen atom. Thus, the correct statement is Option A.
Which one of the following is the correct order of given isotopes?
I. \( T_2 > D_2 > P_2 \quad \text{(order of boiling point)} \)
II. \( T_2 > D_2 > P_2 \quad \text{(order of bond energy)} \)
III. \( T_2 = D_2 = P_2 \quad \text{(order of bond length)} \)
IV. \( T_2 < D_2 < P_2 \quad \text{(order of reactivity with } Cl_2 \text{)} \)
Match the species in Column I with their types in Column II.
