1Complete the table: for each shell K, L, M and N, write the maximum number of electrons accommodated in each of its subshells and the maximum number of electrons in the shell.
2Explain the relationship between electronic configuration based on shell and subshell.
3Define shell, subshell and orbital.
4State Aufbau's principle and write the order of filling of subshells up to 6p.
5Write the subshell configurations of magnesium (atomic number 12) and sulphur (atomic number 16).
6Why does the 19th electron of potassium go into 4s and not into 3d?
7An element has the configuration 1s², 2s²2p⁶, 3s²3p³. Find its atomic number, name it and write its shell configuration.
8How many subshells does the M shell have? Name them and give the largest number of electrons each can hold.