1What is the smallest particle of an element called?
2Are there particles even smaller than an atom?
3Describe the structure of an atom.
4How many electrons can the M shell hold at most? Show the working.
5Write the electron arrangement of chlorine, atomic number 17.
6Why is helium chemically inactive?
7How does the duplet rule differ from the octet rule?
8How do sodium and chlorine reach an octet?
9Why is the arrangement of potassium (19) not 2, 8, 9?