Question

determine the amount of nacl to make 50ml of an isotonic solution.
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Answer 1

A 0.9% NaCl solution is said to be isotonic: when blood cells live in such a medium, the intracellular and extracellular fluids in the cell membrane are in osmotic equilibrium, and there is no net flow or flow of water.

Explanation:

• Isotonic solutions are prepared by combining a volume measured in milliliters and a weight expressed in grams or an equivalent amount of sodium chloride expressed in grams.
• The amount of isotonic solution in milliliters is equal to one gram of sodium chloride dissolved in water.
• All you need to do is multiply the volume and 9% (w/V) to get the mass.
• 9% in decimal is 0.09. Therefore

W/V = 0.09

We are given that the volume is 50 mL so

W = 0.09 * 50 mL

W = 4.5 g NaCl