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ialsoagree t1_iydecbl wrote

Reply to comment by Chromotron in ELI5: Why does stuff dissolve in hot water more? by samuelma

>Yes, they left out some detail and might( have wrongly implied that the total is always negative, i.e. dissolution is endothermic, but this was not what you called out and this is ELI5, not a journal paper.

Sure, you could argue that his statement was specifically saying that hydrogen bonding - or any other force being used to maintain the solvation of the solute - is exothermic.

But my point remains that this isn't a bond between molecules, and that is an ELI5 level topic.

There is no point in chemistry where anyone would ever suggest that solvation involves molecules bonding. No chemistry teacher would ever say that hydrogen bonds, Van Der Waals forces, or any other intermolecular force is "bonding with the liquid molecules" or that "this creates new bonds."

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Chromotron t1_iydftjk wrote

Let me quote Wikipedia, but this is also in agreement with what I learned and sources are given there as well: '''The strength of chemical bonds varies considerably; there are "strong bonds" or "primary bonds" such as covalent, ionic and metallic bonds, and "weak bonds" or "secondary bonds" such as dipole–dipole interactions, the London dispersion force and hydrogen bonding.'''

So bonds are just that, bonds. Some are just stronger or more commonly encountered.

Also, dissolving salts involves their ionic bonds, so if we are pedantic, this part involves even more bonds. But I get some feeling that even ionic bonds are not "bonds" in your mind, only covalent ones?

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ialsoagree t1_iydhqgw wrote

I appreciate that wikipedia may describe it like this, but that doesn't make it an accurate description used in chemistry.

This paper, for example, specifically looks at the differences between chemical and hydrogen bonding (specifically by look at bond strength).

>But I get some feeling that even ionic bonds are not "bonds" in your mind, only covalent ones?

I'd argue that the distinction is more categorical than physical.

All chemical bonds are covalent bonds, there's just a disparity in how much the electrons are actually shared.

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