Final answer:
The molarity of a 5% dextrose in water (D5W) solution is 0.277 M, calculated by dividing 50 grams (mass of dextrose in 1 L) by the molar mass of dextrose. Since dextrose does not dissociate, the osmolarity is equal to the molarity, thus 0.277 Osm.
Step-by-step explanation:
The molarity of a 5% dextrose in water (D5W) solution can be calculated by first determining the number of moles of dextrose present in 1000 mL (or 1 L) of the solution. A 5% solution means 5 grams of dextrose is present in every 100 mL of solution. Therefore, in 1000 mL, there would be 50 grams of dextrose. Using the molar mass of dextrose (180.156 g/mol), the number of moles in 50 grams is calculated by dividing the mass by the molar mass. The molarity is the number of moles per liter of solution.
To find the osmolarity, we need to consider that dextrose does not dissociate into ions in the solution. Therefore, the osmolarity of D5W is equal to its molarity because each molecule of dextrose contributes equally to the osmotic pressure of the solution.
Calculation:
- Moles of dextrose = 50 g / 180.156 g/mol = 0.277 moles
- Molarity (M) = 0.277 moles / 1 L = 0.277 M
- Osmolarity = Molarity since dextrose doesn't dissociate = 0.277 Osm