Question

Which substance is correctly paired with its type of bonding?
(1) NaBr—nonpolar covalent(2) HCl—nonpolar covalent(3) NH3—polar covalent
(4) Br2—polar covalent

Answer 1

1) NaBr is a ionic bond, because most sodium compounds are ionic. Incorrect answer.

2) HCl is polar, not nonpolar. Incorrect answer. 

3)NH3 is a polar covalnet bond because the atoms are not equally shared. So, this answer is correct!!!

Final answer: (3) NH3—polar covalent

Answer 2

Answer: (3) $NH_3$- polar covalent

Explanation: An ionic bond is formed  when the electrons are completely transferred.

A covalent is formed by sharing of electrons and is called as polar covalent when there is electronegativity difference among elements and non polar covalent when there is no electronegativity difference among elements.

(1) $NaBr$—nonpolar covalent: This forms ionic bond by transfer of electrons from $Na$ to $Br$ forming $Na^+$ and $Br^-$ respectively.

2) HCl—nonpolar covalent: This forms a polar covalent bond as the electronegative difference between hydrogen and chlorine is high.

3) $NH_3$ -polar covalent: This forms a polar covalent bond as the electronegative difference between hydrogen and nitrogen is high.

4) $Br_2$—polar covalent: This forms a non polar covalent bond as there is no electronegative difference between same bromine atoms.