It will become almost solid. The ingredients in a box of Jell-O include sugar, flavors and colorings, and gelatine. It was invented there and sold door to door until our town tycoon bought the recipe and patent for a couple hundred dollars. And the rest, as they say, is history. Yes, there is even a Jell-O museum in town.
Gelatine is made from animals used for food.
It's basically finely-ground toenails. Knox Brand Unflavored Gelatine is a convenient way to use the stuff, a packet at a time. Each small box of Jell-O has the equivalent of one packet of Unflavored Gelatine in it. This is a good time to point out that when things get cold, it's harder to taste them. A small box of XYZ Jell-O jells two cups of liquid.