Question

Is $ N{F_3} $ an acid or a base?

Answer 1

Hint: Chemical compounds are classified based on the electron pairs by scientist Lewis. He classified the compounds as Lewis acids and Lewis bases. Lewis acids are the compounds that can accept a pair of electrons and Lewis bases are the compounds that can donate an electron pair. $ N{F_3} $ donates an electron to a pair of nitrogen atoms and can be known as a base.

Complete answer:
Nitrogen is a chemical element with atomic number $ 7 $ and fluorine is a chemical element with atomic number $ 9 $ . Fluorine is the most electronegative element in the periodic table with the value of electronegativity $ 4 $ in the Pauling scale. Thus, nitrogen is less electronegative compared to fluorine.
In $ N{F_3} $ there were one nitrogen atom and three fluorine atoms. Nitrogen occupies the centre as it is less electronegative. The nitrogen has five valence electrons. Out of five electrons, three valence electrons were involved in bond formation with fluorine. The remaining two electrons exist as lone pairs on nitrogen atoms.
These two electrons were ready for the donation to any electron deficient compound.
According to Lewis, the compounds that can be able to donate an electron pair were known as Lewis bases.
Thus, $ N{F_3} $ is a base.

Note:
So many theories were there that describe the nature of chemical compounds. Out of them Lewis theory and Bronsted theory were successful. Lewis theory was based on the electron pairs and Bronsted theory was based on the proton. The compound that can donate an electron pair donor was known as base.