Question

Anions are formed due to gain of electrons by:
A.Metals
B.Non-metals
C.Noble gases
D.None of these

Answer 1

Hint: For this question we must have the knowledge of various terms that are mentioned in options. Anions are negatively charged species. The species which will be deficient in electrons will gain electrons.

Complete step by step solution:
Elements are broadly classified in two ways, metals and non metals.
Metals are found generally toward the left hand side of periodic tables. Some physical properties of metals are:
They are super shiny or lustrous in nature. They are very good conductors of heat and electricity and generally have high melting point and density. All the metals are solid at room temperature except mercury which exists as liquid at room temperature. They are ductile and malleable. Metals never accept electrons. They always have a tendency to lose electrons. Metals always form cations by giving electrons.
Taking about noble gas they are group 18 elements. They have completely filled the valence shell. Elements gain and lose electrons to complete its octet of valence, but noble gases have already fully filled orbital’s, hence they neither gained nor lost electrons and hence cannot form anions.
However nonmetals are electron deficient elements which gain electrons to fill their octet and hence they form anions by gaining electrons.

Note: Since an anion is formed by gain of electron in the shell. After addition of 1 extra electron in the same shell, the repulsion between electron and electro starts because of similar charge. Hence the size of anion increases. So anion is always bigger than the neutral atom and a cation is always smaller than the corresponding atom.