Why salt makes ice cream freeze: the cold that ice and salt create
30seconds
Ice is already cold, so why does salt make ice cream freeze? Because salt does not add cold. It stops the ice and water from staying in balance at 0 °C.
Dissolved ions block water from rejoining the ice while melting carries on. The ice pulls heat from the brine and from your cream until the mixture falls to the new, lower freezing point. Salt water bottoms out near -21 °C. Drag the slider to see where your bucket ends up.
Deep dive · 3 min
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