Question

Calculate the molarity of the final solution of Erythrocin B (MW 879.9 g/mol) if a .5028g sample is dissolved in water diluted to 100 mL in a volumetric flask (Solution 1), and then a 5mL aliquot of the stock solution is diluted to 100mL using volumetric equipment. (solution 2)

Answer 1

Answer:

2.857 × 10⁻⁴ M

Explanation:

First, we will calculate the molarity of the solution 1.

M = mass of solute / molar mass of solute × liters of solution

M = 0.5028 g / 879.9 g/mol × 0.100 L

M = 5.714 × 10⁻³ M

We can find the concentration of the final solution using the dilution rule.

C₁ × V₁ = C₂ × V₂

C₂ = C₁ × V₁ / V₂

C₂ = 5.714 × 10⁻³ M × 5 mL / 100 mL

C₂ = 2.857 × 10⁻⁴ M