Question

If it takes 25.0 mL of 0.050 M HCl to neutralize 34.5 mL of NaOH solution, what is the molarity of the NaOH solution?

Answer 1

The molarity of the NaOH solution is 0.036 M

First, we will write the balanced chemical equation for the reaction

The balanced equation of reaction between HCl and NaOH is

HCl + NaOH → NaCl + H₂O

In the balanced chemical equation above,

It means 1 mole of HCl is required to completely neutralize 1 mole of NaOH

To determine the molarity of the NaOH solution,

We will determine the number of moles of HCl that reacted

From the question,

Volume of HCl = 25.0 mL = 0.025 L

Concentration of HCl = 0.050 M

From the formula

Number of moles = Concentration × Volume

Then,

Number of moles of HCl = 0.050 × 0.025

Number of moles of HCl = 0.00125 moles

This means 0.00125 moles of HCl reacted with 0.00125 moles of NaOH

Now, to determine the molarity (that is concentration) of NaOH,

Number of moles of NaOH = 0.00125 moles

Volume of NaOH = 34.5 mL = 0.0345 L

From the formula

Number of moles = Concentration × Volume

Then,

$Concentration = \frac{Number \ of \ moles }{Volume}$

$Concentration \ of \ NaOH = \frac{0.00125}{0.0345}$

∴ Concentration of NaOH = 0.03623 M

Concentration of NaOH = 0.036 M

Hence, the molarity of the NaOH solution is 0.036 M

Learn more here: brainly.com/question/25008908