Question

If 154.9 grams of KOH exactly neutralizes 262 mL of an aqueous HCl solution, what is the concentration of the HCl solution

Answer 1

10.5M HCl

Step-by-step explanation:

Using the chemical reaction:

KOH + HCl → H₂O + KCl

Where 1 mol of KOH reacts per mole of HCl

We can solve this problem converting the mass of KOH to moles using its molar mass. The moles of KOH added are equal to moles of HCl in the solution. That is:

Moles KOH = Moles HCl

154.9g KOH * (1mol / 56.1g) = 2.761 moles

The molarity of the solution (Moles HCl per liter of solution) is:

2.761moles HCl / 0.262L =

10.5M HCl