Question

which of the following elements, when bonded, would result in a polar covalent bond? electronegativity values of some atoms
2.1
h
1.0
li
1.5
be
2.0
b
2.5
c
3.0
n
3.5
o
4.0
f
0.9
na
1.2
mg
1.5
al
1.8
si
2.1
p
2.5
s
3.0
cl
0.8
k
1.0
ca
2.4
se
2.8
br
c - o
c - h
h - h
c - c

Explanation:

Step1: Recall polar covalent bond concept

A polar covalent bond forms when there is an electronegativity difference between the two bonded atoms.

Step2: Determine electronegativity values

For C - O: Electronegativity of C = 2.5, electronegativity of O = 3.5. Difference = 3.5 - 2.5 = 1.

Step3: Analyze other options

For C - H: Electronegativity of C = 2.5, electronegativity of H = 2.1. Difference = 2.5 - 2.1 = 0.4.
For H - H: Electronegativity of H = 2.1 for both. Difference = 2.1 - 2.1 = 0.
For C - C: Electronegativity of C = 2.5 for both. Difference = 2.5 - 2.5 = 0.

Step4: Identify polar covalent bond

A significant electronegativity difference (usually > 0.5) indicates a polar covalent bond. C - O has the highest electronegativity difference among the options, so it forms a polar covalent bond.

Answer:

C - O