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finlandery t1_iyd555z wrote

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

Random question... Does breaking stuff from solid make stuff slower aka colder? I know nacl+ water makes it colder but is it always like that

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nmxt t1_iyd6ju9 wrote

No it’s not always like that. During dissolving the bonds between the pieces of the solid are broken but new bonds between water molecules and ions are formed. Breaking bonds requires energy, and making bonds releases energy. Therefore, if the pieces of solid are more inclined to bonding with water than with other pieces of the same solid, then overall energy is released and the temperature rises (e.g. sugar). Otherwise, energy is consumed and the temperature falls (e.g. table salt).

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PofanWasTaken t1_iyde6cv wrote

How great is the temperature rise from sugar?

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nmxt t1_iydzxct wrote

Temperature effects of dissolving sugar (and table salt) are very small.

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Belzeturtle t1_iye5e3z wrote

Depends on how much sugar in how much water. But not a lot.

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