Answer:
Three bonds that can be classified as polar covalent bonds are:
Step-by-step explanation:
To classify a bond as polar covalent, the difference in the electronetativities (EN) of the atoms tha form the bond with must be greater than 0.5 and smaller than 1.7 - 1.8 .
Since your question is missing the bonds that you want to classify as polar covalent, I will show you how to do it with a set of bonds that are used in a similar question (which can be found in the internet).
a) H — S bond in H₂S
b) S — O bond in SO₂
c) Mg — Br bond in MgBr₂
d) N — O bond in NO₂
e) C — Cl bond in CCl₄
Covalent bonds are formed by electron sharing between two elements, when their electronegativities do not differe in more than (about) 1.7 in the Pauling scale. If the difference in the electronegativities of the two atoms that form the bond is larger than 1.7 the bond will be more ionic than covalent.
Also, to tell that a covalent bond is polar, the difference in electronegativities of the atoms must be larger than (about) 0.5 in the Pauling scale.
Then, to classify the bonds find the electronegativiities of the atoms that form each bond and classify them as polar covalent is the difference is between 0.5 and 1.7.
a) H — S bond in H₂S
Atom EN
H 2.20
S 2.58
- Difference: 2.58 - 2.20 = 038 ⇒ covalent, nonpolar
b) S — O bond in SO₂
Atom EN
S 2.58
O 3.44
- Difference: 3.44 - 2.58 = 0.86 ⇒ polar covalent
c) Mg — Br bond in MgBr₂
Atom EN
Mg 1.31
Br 2.96
- Difference: 2.96 - 1.31 = 1.65 ⇒ polar covalent
d) N — O bond in NO₂
Atom EN
N 3.04
O 3.44
- Difference: 3.44 - 3.04 = 0.40 ⇒ covalent, nonpolar
e) C — Cl bond in CCl₄
Atom EN
C 2.55
Cl 3.16
- Difference: 3.16 - 2.55 = 0.61 ⇒ polar covalent.