Defn Che

2are negatively charged panicles move outside/ anyaround the nucleus 'in circular or' near circular orbits.

Protons are positively charged particles •resi<g in the nucleuj/ofthe atom.

1. Ngu.Ltgns
   Neutrons are uncharged particles@the nucleusßfthe atom.
2. (i) Nucleus
   A smalb dense/ positively charged gÜg/of the atom is calle$nucleus.!t contains protons and neutrons/
   (ii)Yalg.usg
   When the number of electrons in the outermost shell of the atom of the element is 4 or less than 4, then the valence of that element is equal to the number of electrons in that outermost shell. When the number of electrons in the outermost shell of the atom of the element is greater than 4, the valence of the element becomes 8 minus the number of electrons in that outermost shell.