Question

arrange the highlighted bonds in the table below in decreasing order of polarity. that is, pick 1 for the most polar bond, 2 for the next most polar bond, and so on.

Explanation:

Step1: Recall electronegativity values

Electronegativity of H = 2.1, C = 2.5, O = 3.5, F = 4.0.

Step2: Calculate electronegativity differences

For C - F bond: $\Delta\chi=4.0 - 2.5=1.5$.
For C - C bond: $\Delta\chi=2.5 - 2.5 = 0$.
For C - O bond: $\Delta\chi=3.5 - 2.5=1.0$.

Step3: Arrange by electronegativity difference

Greater $\Delta\chi$ means more polar bond. So C - F (1), C - O (2), C - C (3).

Answer:

C - F: 1, C - C: 3, C - O: 2