Question

1. a sulfuric acid solution that is 65.0% h₂so₄ by mass has a density of 1.55 g/ml at 20°c. what is the molarity of sulfuric acid in the solution? (molar mass h₂so₄ = 98.0 g/mol) a. 3.5 m b. 6.9 m c. 10.3 m d. 12.2 m e. 15.7 m

Explanation:

Step1: Assume solution mass

Assume we have 100 g of the solution. Then the mass of \(H_2SO_4\) is \(65.0\%\) of 100 g, so \(m_{H_2SO_4}=65.0\ g\).

Step2: Calculate moles of \(H_2SO_4\)

Using the molar mass (\(M = 98.0\ g/mol\)), moles \(n=\frac{m}{M}=\frac{65.0\ g}{98.0\ g/mol}\approx0.663\ mol\).

Step3: Calculate volume of solution

The density \(
ho = 1.55\ g/mL\), and mass of solution is 100 g. Volume \(V=\frac{m}{
ho}=\frac{100\ g}{1.55\ g/mL}\approx64.52\ mL = 0.06452\ L\).

Step4: Calculate molarity

Molarity \(M=\frac{n}{V}=\frac{0.663\ mol}{0.06452\ L}\approx10.3\ M\).

Answer:

C. 10.3 M