In a lithium atom, which has three electrons, the ground state electron configuration is 1s2 2s1. This indicates that there are two electrons in the 1s orbital and one electron in the 2s orbital. Each electron is described by four quantum numbers: the principal quantum number (n), the azimuthal quantum number (l), the magnetic quantum number (ml), and the spin quantum number (ms).
Here are the quantum numbers for each of the electrons in a lithium atom in its ground state:
- First Electron (1s):
n = 1, l = 0, ml = 0, ms = +1/2 - Second Electron (1s):
n = 1, l = 0, ml = 0, ms = -1/2 - Third Electron (2s):
n = 2, l = 0, ml = 0, ms = +1/2
Explanation:
– The principal quantum number (n) indicates the energy level of the electron. For the first two electrons in 1s, n = 1, and for the third electron in 2s, n = 2.
– The azimuthal quantum number (l) defines the shape of the orbital. For s orbitals, l = 0.
– The magnetic quantum number (ml) determines the orientation of the orbital. For s orbitals, ml = 0.
– The spin quantum number (ms) describes the spin of the electron, which can be +1/2 or -1/2. In this case, one electron has spin +1/2 and the other spin -1/2 in the 1s orbital, while the electron in the 2s orbital also has spin +1/2.