Which compound most likely contains polar covalent bonds? . the choices are the following: nacl. alf3. br2. nf3

The correct answer for above statement is:

d NF3

(+)NaCl(-) = 0 is linear and the charges cancel so its no polar 

(+3)AlF3(-3) = 0 the charges cancel so its non polar

Br2 is a diatomic element and elements don't have charges so its non polar 

NF3 the N has a lone pair of electrons (:) and so it will repel the fluorine's as fluorine is the most electronegative element there is an unbalance in the charges so NF3 is polar .

Explanation:

In a polar covalent attachment, the particles shared by the atoms absorb a larger amount of time, on the center, closer to the Oxygen nucleus than the Hydrogen nucleus. This is because of the geometry of the molecule and the numerous electronegativity difference between the Hydrogen atom and the Oxygen atom.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.