Modern periodic table (intro)
Periodic Classification (School Level) · Chemistry
Study notes
Element X has electronic configuration 2, 8, 3. Find its group, period and block. Step 1: Valence electrons = 3 → Group 13. Step 2: Shells occupied = 3 → Period 3. Step 3: Last electron in p-subshell → p-block. Step 4: It is aluminium (Al). The table's structure directly reads off electron arrangement.