Chemistry · Atomic Structure
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The relative energies of 4s, 4p and 3d orbitals are in the order:
- A
3d < 4p <4s
- B
4s < 3d < 4p
- C
4p < 4s < 3d
- D
4p < 3d < 4s
The Aufbau principle states that electrons fill lower-energy atomic orbitals before filling higher-energy ones (Aufbau is German for "building-up"). By following this rule, we can predict the electron configurations for atoms or ions. To find the energy of orbitals, we use the (n+l) principle where n= energy level, while l= orbital level.
For 4s: n+l= 4 + 0 = 4
For 3d: n+l= 3 + 2= 5
For 4p: n+l = 4+ 1= 5 (but since the distance of 4p is greater than that of 3d, 3d gets filled first)
Final order: 4s<3d<4p
This order is not correct.
According to the n+l rule, where n is the principal quantum number and l is the azimuthal quantum number, the order of increasing energy of atomic orbitals is given by their sum (n+l). When the sum is same, the orbital with lower n value has lower energy.
For 4s orbital, n=4 and l=0, so (n+l) = 4+0 = 4.
For 4p orbital, n=4 and l=1, so (n+l) = 4+1 = 5.
For 3d orbital, n=3 and l=2, so (n+l) = 3+2 = 5.
Therefore, the order of increasing energy is 4s < 3d < 4p
According to the n+l rule, where n is the principal quantum number and l is the azimuthal quantum number, the order of increasing energy of atomic orbitals is given by their sum (n+l). When the sum is same, the orbital with lower n value has lower energy.
For 4s orbital, n=4 and l=0, so (n+l) = 4+0 = 4.
For 4p orbital, n=4 and l=1, so (n+l) = 4+1 = 5.
For 3d orbital, n=3 and l=2, so (n+l) = 3+2 = 5.
Therefore, the order of increasing energy is 4s < 3d < 4p
This order is not correct.
According to the n+l rule, where n is the principal quantum number and l is the azimuthal quantum number, the order of increasing energy of atomic orbitals is given by their sum (n+l). When the sum is same, the orbital with lower n value has lower energy.
For 4s orbital, n=4 and l=0, so (n+l) = 4+0 = 4.
For 4p orbital, n=4 and l=1, so (n+l) = 4+1 = 5.
For 3d orbital, n=3 and l=2, so (n+l) = 3+2 = 5.
Therefore, the order of increasing energy is 4s < 3d < 4p
This order is not correct.
According to the n+l rule, where n is the principal quantum number and l is the azimuthal quantum number, the order of increasing energy of atomic orbitals is given by their sum (n+l). When the sum is same, the orbital with lower n value has lower energy.
For 4s orbital, n=4 and l=0, so (n+l) = 4+0 = 4.
For 4p orbital, n=4 and l=1, so (n+l) = 4+1 = 5.
For 3d orbital, n=3 and l=2, so (n+l) = 3+2 = 5.
Therefore, the order of increasing energy is 4s < 3d < 4p
Tagged under Chemistry · Atomic Structure · 2012