Why are the atoms on the periodic table set up in columns What is so special about their atomic structure Why is Ne in the last column while Li in the first?

Answer 1

The elements were arranged according to atomic number. And atomic number is equal to the number of protons and electrons.

There is a rule (octet rule), which states that for an atom to be stable, it needs 8 electrons.

The First Group has one excess electron to be stable. Group 7 needs one electron to be stable.

(in short... 1-1=0(stable), 7+1=8(stable))

Group 8 has 8. So it is stable, and located at the end of the table.

Answer 2

The atoms on the Periodic Table are set up in columns based on their electron configuration, which determines their chemical behavior. Atoms in the same column have the same number of electrons in their outermost shell, giving them similar properties. Neon (Ne) is in the last column because it has a full outer electron shell, making it stable and less likely to react with other elements, while lithium (Li) is in the first column because it has one electron in its outer shell, making it highly reactive.