Which of the following is type of bonding involves the complete transfer of a valence electron from a less electronegative atom to a more electronegative one? .
a. ionic bonding.
b. metallic bonding.
c. covalent bonding.
d. hydrogen bonding

Option (a) is the correct answer.

Explanation:

When there is transfer of electrons between the two atoms then the bond formed is known as ionic bond.

In binary atomic systems, there is formation of ionic bond between a metal and non-metals. As a result, there will be high difference in electronegativity between the two atoms.

Therefore, this also shows potential for electrons transfer.

For example, NaCl is an ionic compound and also there is high difference in electronegativity between the Na and Cl atom.

Thus, we can conclude that ionic bonding is a type of bonding which involves the complete transfer of a valence electron from a less electronegative atom to a more electronegative one.

The answer is: a. ionic bonding.

Ionic bond is the electrostatic attraction between oppositely charged ions (cations and anions).  

For example, compound magnesium chloride (MgCl₂) has ionic bond.  

In this example, chlorine is large company, because it has greater electronegativity than magnesium (small company) and take electrons (assets) from it.

Magnesium (Mg) transfers two electrons, became positive cation, to chlorine (Cl), which became negative anion.  

Magnesium is metal from group 2 and chlorine is nonmetal from group 17 of the Periodic table.  

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.