I'll give two explanations. The first explanation needs an understanding of thermodynamics, the second one is easier.
The addition of salt to water results in an increase in "entropy".
This results in a lowering of the freezing point. That means the melting point is lower too. Unfortunately, you need to go through some mathematics to understand this explanation properly.
So, you may prefer this explanation:
When water freezes it forms ice (pure water). The water molecules still in the liquid phase have salt ions mixed in, reducing the concentration of water molecules. So, there's a reduction in water molecules going from liquid phase to the solid at the surface between liquid and ice. That means its harder to form ice and the melting point is lower.
The lower melting point is simply because the concentration of water molecules
in a salt solution is lower than in pure water. It's not because the salt "blocks"
the path of water molecules or affects the chemical bonds. In fact, many different substances can lower the melting point.
Salt lower the freezing point of ice.
Since impurities decrease melting point of solid ,so ice mixed with salt has lower melting point then pure ice .
melting sown
Salt lowers the melting point of ice.
sugar - salt will lower the melting point.
Salt lowers the melting point of ice, making it melt faster and at a lower temperature.
The melting point of ice decreases when salt is added.
In theory, the more salt you add to ice, the more you lower its melting point and the more ice will melt.
when salt is added to ice, salt being an impurity, reduces the inter molecular space between ice molecules. As we know that ice, in order to melt, contracts, i.e reduces the inter molecular space between its molecules. salt increases this activity and so ice melts at a lower temperature than it usually does. i.e salt decreases the melting point of ice.
Adding salt to ice decreases its melting point. Adding salt to the top of ice helps melt the ice faster.
The addition of a solvent to water depresses is freezing point but also depresses its melting point in its solid state (ice) meaning it makes them lower. That is why you put salt on an icy road, so that it will melt below water's ordinary freezing point (0°C). Ice would melt faster in saltwater because the solvent, being salt in this case, would lower the melting point of the ice causing it to melt at a lower temperature. This is counterintuitive when it seems putting salt on ice makes it colder. This is not actually occurring. The ice's melting point is being reduced and therefore melting.
Sodium chloride (salt) lowers the melting point of ice - so it turns back to water at a lower temperature that it would normally.