1Why are the elements of group IA called alkali metals?
2Why are the elements of group IIA called alkaline earth metals?
3Write the electronic configuration of magnesium (atomic number 12) and explain why it is in group IIA.
4Halogens are very reactive, but noble gases do not react. Why?
5What are metalloids? Give three examples and one use.
6What are transition metals, and why are they so called? Give four examples.
7Calcium has atomic number 20. Write its electronic configuration and identify its group and family.
8Which is the odd one out among Li, Na, Cl and K? Give a reason.
9Helium has only two electrons. Why is it still placed in group 0?
10Where are metals, nonmetals and metalloids found in the periodic table? Compare their electrical conductivity.
11In \( ns^2\,np^5 \), what do n, s, p and the raised numbers stand for?