Specifications for lactated Ringer’s solution, which is used for intravenous (IV) injections, are as follows to reach 100. mL of solution: 285−315 mg Na + 14.1−17.3 mg K + 4.9−Q.O mg Ca 2+ 368−408 mg Cl − 231−261 mg lactate, C 3 H 5 O 3 − a. Specify the amount of NaCl, KCl, CaCl 2 · 2H 2 O, and NaC 3 H 5 O 3 needed to prepare 100. mL lactated Ringer’s solution. b. What is the range of the osmotic pressure of the solution at 37°C, given the preceding specifications?

Interpretation: The amount of reagents required and range of osmotic pressure has to be calculated.

Concept Introduction: The mass of the compound is calculated by taking the products of molar mass of the compound to the given mass. The mass of compound can be given by,

Mass of compound(in grams)=Molar mass (in g)×Given mass(in g) 

Colligative properties of a substance include the depression in the freezing point, elevation of boiling-point and osmotic pressure. These are dependant only on the number present and not based on the solute particles present in an ideal solution.

The osmotic pressure can be given by the equation,

Π=MRT

Here,Π=Osmotic pressure           M=Molarity of solution           R= Gas law constant            T=Temperature

Record the given info

Mass of Sodium = 285-315 mg

Mass of Potassium = 14.1-17.3 mg

Mass of Calcium =4.9-6.0 mg

Mass of Chlorine =368-408 mg

Mass of Lactate = 231-261 mg

To calculate the mass of individual elements

Molar mass of Sodium lactate = 112.06 mg

Molar mass of Lactate = 89.07 mg

Molar mass of CaCl2.2H2O= 147.01 mg

Molecular mass of Calcium = 40.08 mg

Molar mass of KCl= 74.55 mg

Molecular weight of Potassium = 39.10 mg

Molar mass of NaCl = 58.44 mg

Molecular mass of Sodium= 22.99 mg

The average values for each ion are,

300.00 mg Na+,15.7 mg K+,5.45 mg Ca2+,388 mg Cl- and 246 mg Lactate

The source of Lactate is NaC3H5O3

Mass of Lactate = 246 mg C3H5O3-×112.06 mg NaC3H5O389.07 mg C3H5O3-=309.5 mg 

The source of Ca2+ is CaCl2.2H2O

 Mass of CaCl2.2H2O= 5.45 mg Ca2+×147.01 mg CaCl2.2H2O40.08 mg Ca2+=20 mg CaCl2.2H2O

The source of K+ is KCl

Mass of KCl= 15.7 mg K+×74.55 mg KCl39.10 mg K+=29.9 mg

Mass of Na+ added =309.5 mg Sodium lactate-246.0 mg Lactate=63.5 mg Na+

Additional amount of Sodium 236.5 mg Na+ is added to get desired 300 mg

Mass of Sodium added =236.5 mg Na+×58.44 mg NaCl22.99 mg Na+=601.2 mg

Mass of Cl- added = 20.0 mg CaCl2.2H2O×70.90 mg Cl-147.01 mg CaCl2.2H2O=9.6 mg

20.0 mg CaCl2.2H2O                 =9.6 mg Cl-29.9 mg KCl-15.7 mg K+          =14.2 mg Cl-601.2 mg NaCl-236.5 mg Na+=364.7 mg Cl-

                    Total Cl-          =388.5 mg

Therefore,

305.9 mg Sodium lactate, 20.0 mg CaCl2.2H2O, 29