Road salt from Peru

 

This has been an exceptionally cold winter for most of the British Isles. Britain is not very good at coping with heavy snowfalls; it does not have many snowploughs and very few vehicles have snow tyres. The traditional British response to snow is to grit the roads (or as many of them as can be gritted with inadequate equipment) with a mixture of salt and grit. This mixture works by lowering the freezing point of ice on the roads. A ten percent salt solution prevents water freezing until the temperature is less than -6 Celsius; if you double the salt content the water will not freeze until a temperature of -16 Celsius is reached, and this is usually enough to cope with the worst of British winters. If temperatures fall below -26 Celsius salt makes no difference and will not prevent ice forming. Continue reading