How to cool a drink 5 times faster than in freezer ("Cooling mixture" experiment)

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How can we cool a bev­er­age 5 times faster than in the freez­er? For this sim­ple life­hack all you’ll need is ice and salt.

Safe­ty pre­cau­tions

To avoid a ther­mal burn, wear pro­tec­tive gloves and long sleeved cloth­ing when work­ing with cool­ing mix­tures.

Reagents and equip­ment:

* ice 750 ml;
* kitchen salt (sodi­um chlo­ride) 250 g;
* 2 glass bowls;
* bev­er­age.

Step-by-step in­struc­tions

In a large beaker mix ice and salt in a ra­tio of 3:1. The cool­ing mix­ture is ready. Now place the bev­er­age in the cool­ing mix­ture. The bev­er­age was at room tem­per­a­ture, but now it has cooled down to -2 °C! Now’s it ready to drink!

Pro­cess­es de­scrip­tion

Cool­ing mix­tures con­sist of two or more sol­id (or sol­id and liq­uid) sub­stances. When they mix, they “take away” warmth and re­duce the tem­per­a­ture from the out­side. The pro­cess­es in which warmth is ab­sorbed from the sur­round­ing en­vi­ron­ment are called en­dother­mic. The cool­ing mix­ture of ice and kitchen salt in the ra­tio of 3:1 can give a tem­per­a­ture of -21 °C.

When we need a high­er tem­per­a­ture, we can change the ra­tio of salt and ice or sur­round the ves­sel con­tain­ing the so­lu­tion with ice or snow, which we sim­ple sprin­kle with salt. A mix­ture of ice and cal­ci­um chlo­ride can re­duce the tem­per­a­ture to -55 °C. Sol­id car­bon diox­ide (dry ice) in a mix­ture with di­ethyl ethеr or ace­tone has a tem­per­a­ture of -78 °C. On the ba­sis of these salts and liq­uids, cool­ing mix­tures are made, and they are used to pre­vent ice build ups.