IMF vs. Intramolecular Forces

[SLai_1I]

When asked to compare the strength molecules, how do we know if the question is referring to IMFs or Intramolecular forces? For example, which molecule is stronger, I2 or F2? F2 has a smaller atomic radius, so its intramolecular forces would be stronger. However, I2 has more electrons, so its LDFs and IMFs would be stronger. Please let me know!

[Arielle Sass 2A]

I would guess by "strength of the molecule" it is referring to intramolecular forces. I think if it was referring to IMF it would be more explicit, because the strength of the molecule on its own doesn't really mean anything in terms of how strongly the molecules are attracted to one another.

[Anthony_3C]

I think if it asks about the bond strengths then it is intramolecular forces. By the way, the ranking of intramolecular strengths is metallic bond > ionic bond > polar covalent bond > nonpolar covalent bond. Also, for ionic bonds, there are also stronger ionic bonds, which are less polarized. If the question asks about melting point, boiling point, vapor pressure, then it's concerning IMFs. Hope this helps!

[Joel Meza 3I]

I believe that question would be asking about intramolecular forces because you are comparing the bonds within two separate molecules (meaning atom with atom in each molecule).

[Joanne Yuh 3I]

I agree with what the people said above. I also think that the question would include a phrase along the lines of "when the molecule interacts with itself" to specify that the question is asking about the intermolecular forces.

[Jonathan Banh 1G]

In the question that you referenced, I believe what they are asking about are the intramolecular forces. This is because they ask about the strength of the molecule, hinting that they are testing you on your knowledge of bond strength, not the interactions that exist between like molecules. What is good is that you understand the difference between intermolecular and intramolecular forces, which outline the forces between molecules and those within molecules, respectively. Thus, I believe the answer would be F2, seeing as how its smaller atomic radius would lead to the bond being shorter and thus stronger within the molecule.

[Tobie Jessup 2E]

I also believe that the question is asking about intramolecular forces based on the language of the question. If the question was wanting to test the students knowledge on IMFs I think there would be specific language about LDFs or other intermolecular forces. The question is most likely questioning knowledge on intramolecular forces due to atomic radii and effective charge etc.

[manisha_joseph_1H]

Hi! I believe in this question, they are referring to intramolecular forces as they give you single molecules to compare rather than multiple molecules interacting with one another (which would be IMF). Additionally, bond strength is referring to the bonds of a single molecule, which also indicates that a question is referring to intramolecular forces.