What Makes Ice Melt the Fastest Salt or Sugar?

What makes ice melt the fastest, salt or sugar?   Salt and sugar will melt ice at the same relative speed... so the answer is that neither does, and you can sprinkle either on your sidewalk.

So, why is it that neither salt nor sugar makes ice melt faster? The reason is because any substance that will produce a freezing point depression can be used to melt ice. It is not the specific substance itself, but rather the affect the substance has on the ice, that have the impact. This is why you sometimes see trucks carrying sand, or even kitty litter, to spread on icy areas. This is done not only in order to promote traction but also to cause the ice to melt.

How Does it Work?

So, why does salt melt ice anyway?

• The chemical compounds that make up salt, usually sodium chloride, disrupt the chemical processes at work in ice, causing it to melt. 
• As the ice melts, the salt mixes with the water that is now present where there once was ice.
• The salt continues the melting action by lowering the freezing point of the ice and water. 

Sugar too will have this melting property on ice, but sugar is more expensive and harder to obtain in large quantities than salt, and as a result, it is not commonly used to melt ice.

It’s strange to think that salt and sugar will melt ice at the same temperature, but the same basic chemical rules apply to both chemicals.  If it became cheaper to melt ice with sand or sugar, it would likely cause a change in the practices of ice melting companies.