It is because all elements in Period 3 have:
So the electron configuration should be written as:
Mg(K,L,M,) = 2, 8, 2,
2 electrons in the K shell and 8 electrons in the L shell
Maximum number of possible electrons in each shell: K - 2 L - 8 M - 8 N - 18
Maximum number of electrons = 2n2, where n is the number of shell (n = 1 for K, 2 for L, 3 for M, and so on) K shell has 2 electrons maximum L shell has 8 electrons maximum M shell has 18 electrons maximum N shell has 32 electrons maximum O shell has 50 electrons maximum P shell has 72 electrons maximum
Phosphorous has 2 elements in K-shell, 8 in L-shell and 5 in M-shell.
If the number of electrons in the M shell is equal to the sum of the electrons in the K and L shells, then the element is Silicon (atomic number 14). It has 4 electrons in the K shell, 8 in the L shell, and 2 in the M shell.
Shell 2, also known as the L shell, can hold up to 8 electrons.
Potassium (K) has an atomic number of 19, which means it has 19 electrons. The arrangement of these electrons in the K, L, and M shells is as follows: the K shell (first shell) holds 2 electrons, the L shell (second shell) holds 8 electrons, and the M shell (third shell) holds the remaining 9 electrons. Therefore, the electron configuration can be summarized as 2 electrons in K, 8 in L, and 9 in M.
Atomic magnesium has three shells.The shell numbering parallels the row number of the first three rows of the periodic table.Magnesium is in the third row. We number these 1,2,3 etc. and because of historical reasons, we also label them as K,L,M ... etc.Electron configuration of magnesium's shells are as follows.1s22s2 and 2p6 (one shell, two orbitals: 2s and 2p, of which the last one has 3 sub-orbitals: 2px, 2py, 2pz, each filled with 2 electrons)3s2With 2 electrons in the first shell, 8 electrons in the second and the last 2 in the 3rd, all 12 electrons of magnesium are accounted for. Done.Aside: The next row is where it gets tricky, but that is a separate question.
If the K and L shells of an atom are full, the atom will have 18 electrons. The K shell can hold 2 electrons and the L shell can hold 8 electrons, totaling 10 electrons in both shells. Therefore, if both the K and L shells are full, there will be 18 electrons in the atom.
Oxygen has 8 electrons in total. The distribution of these electrons in shells KLMN is as follows: K shell has 2 electrons, L shell has 6 electrons, M shell has 0 electrons, and N shell has 0 electrons.
Sice K will have 2 electrons and L will have 8 electrons, the total number of electrons will be 10.
The first shell (K shell) can hold up to 2 electrons, the second shell (L shell) can hold up to 8 electrons, the third shell (M shell) can hold up to 18 electrons, and the fourth shell (N shell) can hold up to 32 electrons.