3.87

[huntercrespo1C]

Which do you predict to have the stronger CX bond, where x is a halogen CF4, CCl4, CBr4
How do you judge the strength of the bond using length when they all are connected by only 4 single bonds?

[tmehrazar]

can someone also explain how to fully do this question!

[Hannah Lee 1B]

The strongest bonds are in CF4, then CCl4, then CBr4. This is because F has the smallest atomic radius, which results in a shorter bond length and a stronger bond.

[Chem_Mod]

This is similar to the HF, HCl, HBr, HI example that Dr. Lavelle did in lecture.

[Fiona Grant 1I]

I'm confused about this. I thought that it would be Br, because Br is the largest atom? If the centers of the F and Br atoms are in the same place in both cases, since the F atom is smaller, there would be a greater distance between the C and F, and F would be the longer and weaker bond. Whereas with Br, there is less distance between C and the larger Br, so the bond is stronger. I don't think my reasoning is correct, but I'm not understanding what the actual reasoning is.

[Natalie Noble 1G]

I see where your confusion is, the thing is, the center of the atoms won’t be in the same place if they are big or small. The number of shells for the atom will help tell you how close it is to another.

The distance between the center of the C will be closer to the center of F because there are not many electron shells covering F’s nucleus.

The distance between the center of the C will be farther from the center of the Br because all of the electron shells are in the way of the nucleus, so their centers are further apart.

That’s why smaller atoms can form a stronger bond, because it takes less distance to get to their nucleus.