A hydrochloric acid solution is 6.00 M and the density is 1.10 g/mL.What is the mass/mass percent concentration of HCl (36.46 g/mol)?

Question

Quizplus · Accepted Answer

First, we need to determine the mass of HCl in one liter of the solution:
Molarity = moles of solute / volume of solution (in liters)
6.00 M = moles of HCl / 1 L
moles of HCl = 6.00 mol/L

The mass of HCl in one liter of the solution can be calculated using the molar mass of HCl:
mass of HCl = moles of HCl x molar mass of HCl
mass of HCl = 6.00 mol/L x 36.46 g/mol
mass of HCl = 218.76 g/L

Since the density of the solution is 1.10 g/mL, the mass of one liter of the solution is:
mass of solution = density x volume
mass of solution = 1.10 g/mL x 1000 mL
mass of solution = 1100 g

The mass/mass percent concentration of HCl is therefore:
mass/mass percent = (mass of HCl / mass of solution) x 100%
mass/mass percent = (218.76 g / 1100 g) x 100%
mass/mass percent = 0.199, or 19.9% (rounded to three significant figures)

Therefore, the answer is Choice C (19.9%).

A Hydrochloric Acid Solution Is 6