Name:

(a) three elements that have a single electron in their outermost shells.

(b) two elements that have two electrons in their outermost shells.

(c) three elements with filled outermost shells.

How could the Modem periodic table remove various anomalies of Mendeleev's periodic table ?

Name two elements you would expect to show chemical reactions similar to magnesium. What is the basis for your choice?

(a) Lithium, sodium, potassium are all metals that react with water to liberate hydrogen gas. Is there any similarity in the atoms of these elements ?

(b) Helium is an unreactive gas and neon is a gas of extremely low reactivity. What, if anything, do their atoms have in common ?

In the modem periodic table, which are the metals among the first ten elements ?