Question

Concentrated HCl is 37% m/m. The density of the solution is 1.19 g/mL. Assume you have 100.0 grams of SOLUTION.

What is the molarity of this solution?
Please show all work!

Answer 1

M HCl sln = 12.0785 M

Step-by-step explanation:

• molarity (M) [=] mol/L
• %mm = ((mass compound)/(mass sln))*100

∴ mass sln = 100.0 g

∴ δ sln = 1.19 g/mL

∴ % m/m = 37 %

⇒ 37 % =((mass HCl/mass sln))*100

⇒ 0.37 = mass HCl / 100.0 g

⇒ 37 g = mass HCl

∴ molar mass HCl = 36.46 g/mol

⇒ mol HCl = (37 g)*(mol/36.46 g) = 1.015 mol

⇒ volume sln = (100 g sln)*(mL/1.19 g) = 84.034 mL = 0.084034 L

⇒ M HClsln = 1.015 mol/0.084034 L

⇒ M HCl sln = 12.0785 M