Why do all the elements of the same group have similar properties? How will the tendency to gain electrons change as we go from left to right across a period? Why?
[3 MARKS]
Each point: 1 Mark
1. Elements in the same group have similar properties due to the fact that they have the same number of electrons in their outermost charge shell.
2. On moving from left to right across a period, metallic character decreases and non-metallic character increases.
3. Since metals tend to lose electrons and non-metals tend to gain electrons, the tendency to gain electrons increases as we move from left to right across a period.