10 Calculate the volume in milliliters of sodium acetate 328

10. Calculate the volume in milliliters of sodium acetate 32.8% required to be added 500 mL of ½ NS to yield a solution with an osmolar strength of 298 mOsm/L?

Solution

10.

concentration of sodium acetate solution = 32.8% by mass

we have 32.8 g in 100 ml solution

or,

328 g in 1000 ml (1 L) solution

for a 1 L solution

density of solution = 1 g/ml

molar mass sodium acetate = 82.03 g/mol

molarity of solution = 32.8 x 1 g/ml x 10/82.03 g/mol

                               = 4.00 M (4000 mM)

to get 298 mOsm/L solution,

Volume of 4000 mM sodium acetate solution needed = 298 x 500/4000

                                                                                     = 37.25 ml