>Correction, or addendum here: the actual dissolution of the salt is an endothermic process, so even if there was no ice, the temperature of water decreases when salt is dissolved.
That's technically true, but it's a rather negligible amount.
Salt has an enthalpy of dissolution of +3.9kJ/mol (1) and a molar mass of 58.44g/mol (2), for roughly 67J/g.
For comparison, water=ice has an enthalpy of fusion of 334J/g (3), and you'll be adding at least three times more ice than salt (as max salt concentration is around 25% g/g (4) ). When you take this into account, it's a whole order of magnitude of difference, so for practical purposes you can outright ignore the heat being consumed by the dissolution of the salt.
That's technically true, but it's a rather negligible amount.
Salt has an enthalpy of dissolution of +3.9kJ/mol (1) and a molar mass of 58.44g/mol (2), for roughly 67J/g.
For comparison, water=ice has an enthalpy of fusion of 334J/g (3), and you'll be adding at least three times more ice than salt (as max salt concentration is around 25% g/g (4) ). When you take this into account, it's a whole order of magnitude of difference, so for practical purposes you can outright ignore the heat being consumed by the dissolution of the salt.
Sources:
1. https://chem.libretexts.org/Bookshelves/Physical_and_Theoret...
2. https://en.wikipedia.org/wiki/Sodium_chloride
3. https://en.wikipedia.org/wiki/Enthalpy_of_fusion
4. https://en.wikipedia.org/wiki/Saline_water