Respuesta :
Answer: The molarity of ethyl alcohol in cough syrup is 1.08 M
Explanation:
We are given:
(m/m) of ethyl alcohol = 5.0 %
This means that 5 g of ethyl alcohol is present in 100 g of solution.
To calculate volume of solution, we use the equation:
[tex]\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}[/tex]
Density of solution = 0.9928 g/mL
Mass of solution = 100 g
Putting values in above equation, we get:
[tex]0.9928g/mL=\frac{100g}{\text{Volume of solution}}\\\\\text{Volume of solution}=100.725mL[/tex]
To calculate the molarity of solution, we use the equation:
[tex]\text{Molarity of the solution}=\frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}[/tex]
We are given:
Mass of solute (ethyl alcohol) = 5 g
Molar mass of ethyl alcohol = 46.07 g/mol
Volume of solution = 100.725 mL
Putting values in above equation, we get:
[tex]\text{Molarity of solution}=\frac{5g\times 1000}{46.07g/mol\times 100.725mL}\\\\\text{Molarity of solution}=1.08M[/tex]
Hence, the molarity of ethyl alcohol in cough syrup is 1.08 M
