Question

What is the molarity of a HCl solution that contains 8.53 g of HCl in 372 mL of solution?

Answer 1

Answer:

M = 0.629 M

Explanation:

To calculate the molarity of any solution, you need to use the following expression:

M = n/V (1)

Where:

M: Molarity or concentration of solution (mol/L or M)

n: moles of solute (moles)

V: Volume of solution (In Liters)

But in order to use the above expression, we need to calculate the moles of the HCl, which is calculate with the following expression:

n = m/MM (2)

Where:

m: mass of the HCl (g)

MM: molar mass of HCl (g/mol)

The reported molar mass of HCl is 36.46 g/mol.

Calculating first the moles, using (2) we have:

n = 8.53 / 36.46 = 0.234 moles

Now that we have the moles, we can calculate the molarity, but first we need to pass the volume from mL to Liter:

V = 372 / 1000 = 0.372 L

Finally, let's calculate the molarity using (1) and the value of the obtained moles:

M = 0.234 / 0.372

M = 0.629 M

And this is the molarity of the HCl solution

Answer 2

First you find moles of HCl.

8.53gHCl(1 mol HCl/36.46gHCl)=0.234mol HCl

Then since molar it is mol/L you divide the number on moles of HCl by the amount of solution in L (0.372L).
Good luck!