Quora is a Q/A site. Can you comment on the fallac(y,ies) in the question shown?

Why aren't materials with the highest melting points also the strongest materials since both traits depend on having strong bonds between atoms?

I thought this question would be a refreshing change of pace. Those who answered had to find the fallacy and work around it. Can you see the fallacy?

One apparent fallacy lies in the absence of providing a definition for "strongest". In Materials Science, strongest could be a proxy for either tensile strength, hardness, toughness, etc.
The selected definition directly impacts the conclusion. For example, diamond is regarded as a very hard mineral, having exceedingly high resistance to scratching and a keen ability to score other materials. However, diamond burns readily and will shatter upon impact, e.g., upon being struck by a hammer. The element Tungsten has a high tensile strength and also a very high melting point; this would then illustrate the relationship between high bond strength and melting points. Alloys such as Maraging Steel, having high tensile strength and melting points, also illustrate this.

If however, one makes the simplifying assumption that "strongest" refers exclusively to tensile strength, then one must recognize that while melting point and tensile strength of different materials are highly correlated, they are not directly (or absolutely) correlated. (Certain Polymeric materials such as nylon have high tensile strengths yet low melting points.) Thus implicit, is the fact that there are other (or more nuanced) forces than bond strength at play.

Why aren't materials with the highest melting points also the strongest materials since both traits depend on having strong bonds between atoms?

Perhaps playing Captain Obvious here, but it is begging the question (actually double). The question assumes 1) materials with the highest melting points aren't also the strongest materials and 2) both traits depend on having strong bonds between atoms.

I'll pass. Ask a chemist!

Good thought-provoking question, though.

I'm curious why this required finding a fallacy to answer. If I consider the following assumptions true:

Materials with high melting points must have strong bonds between their atoms.
Strong materials must have strong bonds between their atoms.
The strongest materials are not the materials with highest melting points.

The logical conclusion is that the strength of the bond between atoms isn't the sole determining factor for either of those traits, and there is at least one other factor that is critical to at least one of them.


Or, is that the fallacy in a nutshell? The belief that because A is necessary for B, then A implies B?