In which of the following energy of 2s orbital is minimum?
In which of the following energy of 2s orbital is minimum?
The correct option is C 3) K
Explanation for Correct answers
Correct option (c)
Energy of Orbital
- The energy of orbital in multi-electron types of atoms is dependent on both principal quantum number (n) or shells and azimuthal quantum number (l) or subshells.
- For a given principal quantum number let’s say 3, the different subshells 3s, 3p and 3d will have different energies.
- The reason behind different energies between the various subshells of the same shell is that there exists a mutual repulsion among the electrons in multi-electron atoms.
- The stability of multi-electron atom is due to the bigger magnitude of attractive force between nucleus and electrons as compared to the forces of repulsion between electrons of the inner shell and outer shell.
- For the electron in the same orbital, attraction is more for a larger atomic number. An increase of attraction decreases the energy of the orbital and the electron present in it.
- Arranging them in the increasing order of atomic number
- Energies of the orbitals in the same subshell decrease with an increase in the atomic number.
Hence, 2s orbital (energy level) of potassium will have minimum energy than others, due to high atomic number.
Explanation for Incorrect answers
1) Lithium has low atomic number( i.e. 3) so, it will have high energy 2s orbital. Hence, option 1 is incorrect.
2) Since Sodium has low atomic number than potassium, so it will have high energy 2s orbital. Hence, option 2 is incorrect.
4) In Hydrogen, the energy of orbital is only dependent on principal quantum number, and so the 2s and 2p orbital in hydrogen atom have the same energy.
The 1s orbital in the hydrogen atom corresponds to the most stable condition and is called the ground state, Therefore, option 4 is incorrect.
3) K
Explanation for Correct answers
Correct option (c)
Energy of Orbital
- The energy of orbital in multi-electron types of atoms is dependent on both principal quantum number (n) or shells and azimuthal quantum number (l) or subshells.
- For a given principal quantum number let’s say 3, the different subshells 3s, 3p and 3d will have different energies.
- The reason behind different energies between the various subshells of the same shell is that there exists a mutual repulsion among the electrons in multi-electron atoms.
- The stability of multi-electron atom is due to the bigger magnitude of attractive force between nucleus and electrons as compared to the forces of repulsion between electrons of the inner shell and outer shell.
- For the electron in the same orbital, attraction is more for a larger atomic number. An increase of attraction decreases the energy of the orbital and the electron present in it.
- Arranging them in the increasing order of atomic number
- Energies of the orbitals in the same subshell decrease with an increase in the atomic number.
Hence, 2s orbital (energy level) of potassium will have minimum energy than others, due to high atomic number.
Explanation for Incorrect answers
1) Lithium has low atomic number( i.e. 3) so, it will have high energy 2s orbital. Hence, option 1 is incorrect.
2) Since Sodium has low atomic number than potassium, so it will have high energy 2s orbital. Hence, option 2 is incorrect.
4) In Hydrogen, the energy of orbital is only dependent on principal quantum number, and so the 2s and 2p orbital in hydrogen atom have the same energy.
The 1s orbital in the hydrogen atom corresponds to the most stable condition and is called the ground state, Therefore, option 4 is incorrect.
