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A 20.0 mL solution of NaOH is neutralized with 24.1 mL of 0.200 M HBr. What is the concentration of the original NaOH solution

User Convict Moody
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1 Answer

27 votes
27 votes

Answer:

0.241 M

Step-by-step explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

HBr + NaOH —> NaBr + H₂O

From the balanced equation above,

The mole ratio of acid, HBr (nₐ) = 1

The mole ratio of base, NaOH (n₆) = 1

Finally, we shall determine the concentration of the NaOH solution. This can be obtained as follow:

Volume of base, NaOH (V₆) = 20 mL

Volume of acid, HBr (Vₐ) = 24.1 mL

Concentration of acid, HBr (Cₐ) = 0.2 M

Concentration of base, NaOH (C₆) =?

CₐVₐ / C₆V₆ = nₐ/n₆

0.2 × 24.1 / C₆ × 20 = 1/1

4.82 / C₆ × 20 = 1

Cross multiply

C₆ × 20 = 4.82

Divide both side by 20

C₆ = 4.82 / 20

C₆ = 0.241 M

Therefore, the concentration of the NaOH solution is 0.241 M

User Jakobk
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