Chapter 11, Problem 29A

Interpretation Introduction

Interpretation: Purpose of additional orbitals in hydrogen even if it has 1 electron is to be explained.

Concept introduction: 3-D space around nucleus in which probability of finding an electron of particular energy is maximum, is called orbital. Quantum numbers are group of 4 numbers which tell everything about electron present in an atom. Principal quantum numbers indicates principal energy level in which electron in present. It is denoted by $n$ . In an atom principal quantum number tells about size of orbital, approximate energy of electron in orbital and the number of electron an orbital can contain.

Answer to Problem 29A

Additional orbital are excited states of hydrogen atom which are occupied only when some discrete energy is given to it.

Explanation of Solution

Orbital is maximum probability space for electrons where it can be found. When hydrogen in ground state its electron is present in the lowest energy shell that is $1s$ . But on giving discrete energy to the atom, electron can be excited and it can occupy the additional orbital present in the hydrogen atom. Additional orbital are excited states of hydrogen atom.

So on excitation of hydrogen atom electron can occupy $2s$ or $2p$ orbital. But at one time its one electron can be any one orbital.

Conclusion

Additional orbital are excited states of hydrogen atom which are occupied only when some discrete energy is given to it.