system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5 “Why does salt make ice colder but we use it to melt ice on sidewalks?”

Edit: Wow I love this sub, thanks for all the answers!
gpt
Saltwater freezes at a lower temperature than fresh water. Ocean water freezes at around -2° C, and higher concentrations of salt decrease that temperature. This allows water to go colder before it turns into ice. So, if you put a bunch of salt in water, that water can get colder than normal because it does not freeze. Similarly, you put salt on the ground so that when it snows, the snow melts not because the salt warms it, but because it makes it so that it needs to be colder to remain in snow form.