Q&A for How to Keep Ice from Melting

The towel keeps cold air in and warm air out if you seal it correctly.

Yes, adding salt to the ice will lower its melting point and make it colder. As the ice block melts, it will get colder because the energy is being used to break the solid state bonds.

Encase it in Styrofoam and thick towels. If you want to go full on, slide ice-packs between a Styrofoam box and a the thick towel that it's wrapped in. This should stay cold for several hours, depending on how well sealed the box is, the outside temperature, the quality of the insulation materials, and the size of the ice cube.

Styrofoam is a good insulator, so it keeps its contents at or near their original temperature for a long time.

Yes, it just won't melt as quickly. The towel will help to keep the cold air in and the warm air out for longer than if you didn't use a towel.

Put salt on the ice. It may sound like it won't work, but actually, salt lowers the temperature.

The best way is to keep inside of a freezer. If you don't have one, put it in a closed container with ice bags inside.

It depends on the temperature of the container or room. Higher temperatures mean the ice will melt faster.

People would wrap large blocks if ice in sawdust or would keep the ice underground where it was cooler. Ice did not last long and was quite rare in the summer.

Salt actually expedites the melting process.

Just a sprinkle should be fine. Salt is very good at slowing the melting process but not to much.

Around 0 degrees Fahrenheit should be good. That is the ideal temperature for an average freezer.

You can do an experiment where you test which ice melts faster, with sugar or salt.

Wood shreds are easily flammable, and I believe that if anything, they will only catch heat.

No, it is an insulator so the ice will not melt.

Yes, ice will melt if placed in the microwave.

No, it will make the ice melt faster.

You could add lots of salt to it.

Yes. The more mass, the more that has to be melted. It also has a reduced surface area relative to mass, so there is less heat exposure.

You can try using wax paper and aluminum foil. Wax is a poor conductor of heat and aluminum foil reflects heat. You could also use a stone container because they don't let heat into the box easily. Without moving air, there won't be much thermal energy to melt the ice.

It doesn't. It actually speeds up the ice melting by raising the freezing point of the water. In a cooler this will get your contents cooler quicker because the newly formed water will cover more surface area than it would previously in ice form.

Yes, put it in the freezer. Or, wrap in foil and a towel and put it in a cellar or other cold underground place that has a constant cold temperature.

Yes. Just don't place the box under direct sunlight, and it will keep your ice cream cool for up to 24 hours.

Any kind of salt. It is your choice. Cheap salt is fine, no need for fancy Himalayan salts.

Felt will most likely keep ice solid for the longest time, as it is a natural insulator. It is good because it keeps warm air out and preserves the cold air made by ice, allowing it to cool off continually.

Sawdust will act as an insulator. Sawdust is used to keep big chunks of ice from freezing together. If you grind Styrofoam as small as sawdust, it will do the same thing but is pretty messy and hard to control.

It would help, but not nearly as much as a fabric towel. Paper towels would not have as durability of them staying intact, and even if they did, they would take more work than it would be worth in the end.

No, but it slows it down. This is because salt water freezes at a lower temperature.

It needs to be kept at 32ºF or below, to keep water frozen, and lower than that to keep saltwater ice frozen.

Yes, plastic buckets serve as a good insulator for ice and can keep the warm air out.