De-icer is made of calcium chloride or other chemical like it mixed into water. Some are simply salt crystals or glycol. All lower the freezing temperature of water. If an earthworm is placed into it, the water that is in the worm will leave and try to equalize the water in the worm with the water outside the worm. That will not work and so the worm is "sucked" dry of water.
YES! its just like putting salt on a snail.
They do unless they stay close to the moisture in the ground.
No they have moist skin otherwise they would dry out.
When it rains, earthworms are essentially drowning under the ground because they breathe through their skin, so they come up onto land in order to breathe. Then they get stuck there and die and dry up.
There are several pond deicer options available for someone to purchase. Depending on the size of the pond or water source a person wants the pond deicer for, the size would make a difference.
they crawl onto the earths surface and sit there to fry to death
earth worm has a fluid that ozees out and keep earthwor skin dry
Dead plants and animals would pile up if it were not for the earthworms.
If it is a rainy day some might show up. You can buy earthworms too.
you can but are wasting your money
Earthworms come up to the surface during rain because the ground is saturated with water. If they stay underground, they will drown.
Mostly glycol alcohol.