Given the following bond lengths in pm:
C-C,154;C =C,134;Cl-Cl,199
What is the best estimate of the C-Cl bond length in CCl₄ in pm?

Question

Given the following bond lengths in pm: C-C,154;C =C,134;Cl-Cl,199 What is the best estimate of the C-Cl bond length in CCl₄ in pm? A)353 pm B)706 pm C)167 pm D)333 pm E)177 pm

Quizplus · Accepted Answer

The C-Cl bond in CCl₄ is expected to be shorter than Cl-Cl bond due to the presence of the carbon atom. Since carbon forms a double bond with another carbon in the molecule, it has some double bond character and hence is shorter than a single bond. Therefore, we can expect the C-Cl bond to be slightly longer than the sum of the atomic radii of carbon and chlorine, which is 154 + 99 = 253 pm. The answer closest to 253 pm is E)177 pm, which is the best estimate of the C-Cl bond length in CCl₄.

Given the Following Bond Lengths in Pm