at what degrees does salt water freeze/?

Question

the freezing point of salt water

Answer 1

The freezing temperature of salt water depends on how much salt you put in. Oceanographers define the "salinity" of water as the number of grams of salt per 1000 grams of water. (Since 1000 grams of water is almost exactly 1 liter, it's also grams of salt per liter).

Here's a table which gives the freezing point of water at a number of different salinity's:
S(g/kg) 0
T(freezing) (C) 0
S(g/kg) 10
T(freezing) (C) -0.5
S(g/kg) 20
T(freezing) (C) - 1.08
S(g/kg) 30
T(freezing) (C) -1.63
S(g/kg) 35 (Sea Water)
T(freezing) (C) -1.91
Away from rivers and glaciers, the ocean has a salinity of about 35. The Atlantic is about 1 salinity units saltier than the Pacific. So ocean water freezes at about -1.91 degrees C

If you have a liter of water, you should expect the freezing temperature to drop by .054 degrees for each gram of salt.

Answer 2

Adding salt *lowers* the freezing point. Pure water (that is, when only H2O moleules are present) freezes at 0 degrees Celcius (32 degrees F). The ocean, which is about 3.5% salt, freezes near -2 C (or about 29 F).

Answer 3

Depends on the amount of salt in the water

Answer 4

There is no saying at all. Sometimes, salt water may absolutely NEVER freeze...

Answer 5

This is a classic 'Science Fair' type of experiment. My daughter did it when she was about 10, the saltier it is, the lower the temp.

Answer 6

-1.9 c