Will Salt Water Freeze?

Most recent answer: 04/25/2013

Q:
I am currently conducting a science assignment on wether salt affects the freezing rate of water. So i have placed an ice cube tray in the freezer containing different amounts of salt. Will it all eventually freeze or will I need to lower the temperature of the freezer to work? My highest amount is 2 1/2 teaspoons of salt to 40ml of water.
- Kara (age 15)
A:
Your highest amount is pretty close to what's called a saturated solution, as much salt as will stay dissolved in liquid water. That freezes at about -21°C, at least if it sits long enough, leaving just ice and salt crystals, no liquid. Your freezer can probably get that cold, but you might have to set it to its coldest setting.

Mike W.

(published on 04/25/2013)