The snail will not move for a while and it wont be in a closed shell. You will definatly be able to see its body which will be greyish instead of pinkish. It will also be laying at the bottom of the tank, half-open, greyish, motionless, and life-less. You will also smell an oder in most cases. Hope this helps!
I assume you mean the Golden Apple snail.
Use that link, it is a picture of an apple snail. I keep them as pets, so you might not know, but they have different sexes unlike most snails.
It depends. To see if they have died, there are 2 factors. 1. The apple snail is completely out of its shell. 2. The apple snail isn't moving and it smells like rotten eggs.
Snails look very frail and pale when they die. These snails also look very limp and wrinkly when they die.
~(_)xx} Kinda like that
The only way to tell if a snail is dead is to sniff the snail, if it gives off a strong, odorous scent, it is most likely dead.
It will stink like dead fish.
if it hasn't moved in a week it is probably dead
Not necessarily as lots of snails float from time to time. Pick it up and touch the foot with your finger and see if it reacts.
put water in it or shake the snail.
TOUCH IT IF IT MOVES OR BUBBLES UP ITS ALIVE
Snails that do not move for a day are definitely not well. An easy way to tell is to pick it up and smell it, and if it smells rotten, then its dead or dieing. Don't inhale too deeply, as rotting snail smell is one of the most disgusting smells you can smell.
Snails stink horridly when they die. If you have the stomach, you can pick he/she up and get a little whiff. Trust me, you'll know then if he/she is dead or not.
A baby garden snail will not move at all when it is dead. One way of establishing whether it is dead or alive is trying to move it with a stick.
it eats dead animals
probably not
yes,depending on what type of snail. If its a small snail then consider it dead but if its a big ugly snail then it should be fine. In other words, check with the vet. :)