They are used to make plane bodies.
Some are used for electrical wires eg copper because they are good conductors of electricity.
Used in building materials.
used to make jewelry eg gold and silver<span />
Answer: This is because the number of shell increases .
Explanation: On moving from left to write on the periodic table the reactivity of non metals increases because number of shells increases and the force with which the nucleus hold electrons decreases.
This process is called evaporation as I believe