What do you think is the appropriate NaCl concentration for IV fluid? Why?

See the answer below

Explanation:

The appropriate NaCl concentration for IV fluid is 0.9% NaCl.

This is because this concentration of NaCl is isotonic to the human body and is safe to be administered as an intravenous fluid into the body.

An isotonic solution is a solution that is neither too concentrated for the cells of the body to lose water into the surrounding solution nor too diluted for the cells to start absorbing water from the surrounding solution. The solution is in equilibrium with the cytosols of the body cells.