What happens when a cell is placed in a solution containing 5% NaCl

Hello sonkist

what happens when a cell is placed in a solution containing 5% NaCl ?

That solution is hypertonic relative to cells, which will shrivel-up and die.
An often used method of preserving foods (pickling in brine).

An animal cell would certainly shrivel-up and die, but halohiles would not only survive but thrive. Halophiles are organisms (bacteria & archaea) that “like” high salt conditions. Some groups of archaea require at least a 2 M salt concentration to grow. (5% is about 1 M)
See Halophile - Wikipedia, the free encyclopedia