Isotonic saline solution has a mass % NaCl concentration of 0.900 %. Assuming its density is 1.00 g/mL, what is its molarity?

Question

Quizplus · Accepted Answer

To calculate the molarity, we need to convert the mass % concentration to moles of solute per liter of solution:

- Mass % concentration = 0.900% = 0.00900 g NaCl/g solution
- Assume we have 1 L of solution, then the mass of NaCl is 0.00900 x 1000 g = 9.00 g
- The molar mass of NaCl is 58.44 g/mol, so the number of moles of NaCl is 9.00 g / 58.44 g/mol = 0.154 mol
- The volume of the solution is 1 L = 1000 mL
- Therefore, the molarity is: 0.154 mol / 1000 mL = 0.154 M

Isotonic Saline Solution Has a Mass % NaCl Concentration of 0.900