Effectively, the salt molecules stop some of the water molecules from touching the part of the water that is becoming solid. At 32 degrees Fahrenheit, water molecules enter and leave the freezing state at an equal rate.Continue Reading
When salt is present, however, it upsets this process, as it prevents the molecules from coming together. It is like having a handful of weak magnets. They come together easily if nothing is in between them, but if other things are present, such as marbles, the magnets have a more difficult time attracting one another.
Water with salt in it has to be colder for it to solidify. Lowering the temperature of water makes the molecules move more slowly. In time, the molecules entering and leaving the solid part of the water equal out again, as everything is moving more slowly, and it is able to freeze.Learn more about States of Matter
When salt is added to water, it raises the boiling point, requiring the salt water to reach a higher temperature to boil. The boiling point increases as more salt is added to the water.Full Answer >
Sugar is able to melt ice because it disrupts the equilibrium of the water molecules and causes the freezing process to slow down, resulting in conditions that favor the melting process over the freezing process. The addition of a foreign molecule, such as sugar, results in a lower freezing point.Full Answer >
When water freezes, the molecules slow down and assume a fixed position, although not quite in the way that one might think. Water is made of molecules with two hydrogen atoms and an oxygen atom, but those molecules don't just stop moving as units. One would think they would all stop, because the Third Law of Thermodynamics says that entropy drops with temperature, getting close to zero. However, ice does not show that property, which is one reason why ice is the only solid less dense than its liquid state.Full Answer >
The hydrogen bonding gives water a structure with considerable space between the molecules, making it expand in size and become less dense in a solid state than in a liquid one. Because water is denser than ice, ice cubes float on the surface of water. Hydrogen bonds link each water molecule to an average of 3.4 other water molecules, and the lattice that forms when water freezes has a lot of empty space inside it.Full Answer >