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Salt is routinely used to melt snow and ice on winter roads. But what is happening at the molecular level to cause this helpful change of state?Key facts
- When salt is added to water it lowers the freezing point.
- Spreading salt on roads causes the ice to melt.
- Salt weakens the rigid lattice structures of ice and the molecules become disordered.
- Salt becomes less effective if temperatures fall below -7 degrees Celsius.
Transcript
Ever wondered why salt makes roads and pavements less slippery?
The answer lies in the differences in chemical properties of water and water solutions.
When salt is added to water it lowers the melting and freezing point.
This is due to the salt interacting with the water, creating a solution.
Water normally freezes ...
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