Among 4p, 4s, 3p and 3d orbitals, the 3d orbital has the least energy.
Among 4p, 4s, 3p and 3d orbitals, the 3d orbital has the least energy.
The correct option is B False
Aufbau principle
The Aufbau principle dictates the manner in which electrons are filled in the atomic orbitals of an atom in its ground state. It states that electrons are filled into atomic orbitals in the increasing order of orbital energy level. According to the Aufbau principle, the available atomic orbitals with the lowest energy levels are occupied before those with higher energy levels.
Lower values correspond to lower orbital energies. If two orbitals share equal values, the orbital with the lower n value is said to have lower energy associated with it.
The order in which the orbitals are filled with electrons is: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, and so on.
- For 3p orbital, n=3 and l=1, so (n+l) value is 4.
- For 4s orbital, n=4 and l=0, so (n+l) value is 4.
- For 3d orbital, n=3 and l=2, so (n+l) value is 5.
- For 4p orbital, n=4 and l=1, so (n+l) value is 5.
For the same value of (n+l), an orbital with a higher n value will be having greater energy.
The increasing order of energy of given orbitals is: 3p < 4s < 3d < 4p.
So, 3p has the least energy among 3p, 3d, 4s and 4p.
Therefore, the given statement is false. i.e., among 4p, 4s, 3p and 3d orbitals, the 3p orbital has the least energy.
Aufbau principle
The Aufbau principle dictates the manner in which electrons are filled in the atomic orbitals of an atom in its ground state. It states that electrons are filled into atomic orbitals in the increasing order of orbital energy level. According to the Aufbau principle, the available atomic orbitals with the lowest energy levels are occupied before those with higher energy levels.
Lower values correspond to lower orbital energies. If two orbitals share equal values, the orbital with the lower n value is said to have lower energy associated with it.
The order in which the orbitals are filled with electrons is: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, and so on.
- For 3p orbital, n=3 and l=1, so (n+l) value is 4.
- For 4s orbital, n=4 and l=0, so (n+l) value is 4.
- For 3d orbital, n=3 and l=2, so (n+l) value is 5.
- For 4p orbital, n=4 and l=1, so (n+l) value is 5.
For the same value of (n+l), an orbital with a higher n value will be having greater energy.
The increasing order of energy of given orbitals is: 3p < 4s < 3d < 4p.
So, 3p has the least energy among 3p, 3d, 4s and 4p.
Therefore, the given statement is false. i.e., among 4p, 4s, 3p and 3d orbitals, the 3p orbital has the least energy.
