What would happen to a clam if you tried to open it while it’s alive?

Most clams are shucked(opened for consumption) while they are alive, this however does not instantly kill them because they usually are just having their muscles severed from the shell during this process, so they could potentially live longer.
Technically speaking the clam could potentially continue to live in the right marine environment after being shucked if only the muscles were severed, but the only place I can see that happening is in a science lab.
Whether they experience pain is still a highly debated topic, but I highly doubt they do because while they do have a nervous and digestive system with tiny organs, such as a heart and kidneys, they don’t have a brain.
You need a brain to process what the nerves are feeling. Their nerves are more of a reactionary system that respond to stimuli. For example, if a clam is alive and partially open and you tap on it, the vibration will make their nerves react by closing.
To help put this in perspective…
When a human has surgery they are given anesthesia, which temporarily blocks all of your pain signals to the brain. When anesthesia wears off or doctor reverses it, you mentally continue from the moment you went under. It feels like a minute has passed, even though it’s often been 5–10 hours. You don’t remember a single thing and during the surgery you don’t experience any pain.
So if a person with a brain experiences no pain when they have their pain signals blocked, you can be pretty sure a clam, oyster, mussel or scallop is not experiencing any pain with no brain at all.

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