The bought clams were kept for 2 hours, then changed to clean water and added salt, and then they were brushed with a brush and found that they stopped talking. Are they dead? Can they still eat?
It's not light salt water. Add a little more salt water (the sea water is bitter), stir it well and then add the clams. Then don't disturb them, they will come out soon.
The closed ones must be alive (unless they are dead for a long time, and they are all covered with soil). The dead ones usually have their mouths slightly open and smell fishy.