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The 3rd period contains 2 of the 3 orbitals for the third sublevel. It has the s and p orbitals in it.
Electrons occupy orbitals in a definite sequence, filling orbitals with lower energies first. Generally, orbitals in a lower energy level have lower energies than those in a higher energy level. But, in the third level the energy ranges of the principal energy levels begin to overlap. As a result, the 4s sublevel is lower in energy than the 3d sublevel, so it fills first.
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There are one 3s orbital, three 3p orbitals, and five 3d sublevels.
There are five different d orbitals within the 3d sublevel: 3dz², 3dxz, 3dyz, 3dx²-y², and 3dxy.
There are 2, 6 and 10 electrons in the 3s (1 suborbital), 3p (with 3 suborbitals: 3px, 3py, 3pz) and 5 sub orbitals in the 3d orbital: this makes a total of 18 electrons in 9 suborbitals
The 3rd period contains 2 of the 3 orbitals for the third sublevel. It has the s and p orbitals in it.
When the 3d orbitals are completely filled, the new electrons will enter the 4s orbital before filling the 3d orbitals. This is because the 4s orbital has a lower energy level than the 3d orbitals, making it the first choice for accommodating additional electrons.
Electrons occupy orbitals in a definite sequence, filling orbitals with lower energies first. Generally, orbitals in a lower energy level have lower energies than those in a higher energy level. But, in the third level the energy ranges of the principal energy levels begin to overlap. As a result, the 4s sublevel is lower in energy than the 3d sublevel, so it fills first.
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Zero. Calcium has two electrons in its 4s sublevel, and none in the 3d sublevel. The 3d sublevel doesn't start filling until after the 4s sublevel is filled.
The lowest energy level that contains d orbitals is the third energy level. Within the third energy level, starting with the 3d sublevel, the d orbitals become available.
There is no such level as 2d. In 1st level there is just 1s. In the 2nd level there is 2s and 2p. Only in the 3rd level is there 3s, 3p and 3d. The sublevels of 3d are 3 dxy dyz dxz d(x2-y2) dz2 so 5 sublevels of 3d.
There are one 3s orbital, three 3p orbitals, and five 3d sublevels.