An aqueous solution of sodium hydroxide is standardized by titration with a 0.198 M solution of perchloric acid. If 17.5 mL of base are required to neutralize 15.2 mL of the acid, what is the molarity of the sodium hydroxide solution?

The molarity of sodium hydroxide solution is 0.172 M

Explanation:

Step 1: Data given

Molarity of perchloric acid (HClO4) = 0.198 M

Volume of HClO4 = 15.2 mL = 0.0152 L

Volume of NaOH = 17.5 mL = 0.0175 L

Step 2: The balanced equation

HClO4 + NaOH → NaClO4 + H2O

Step 3: Calculate molarity of the sodium hydroxide solution

a*Cb*Vb = b*Ca*Va

⇒with a = the coefficient of HClO4 = 1

⇒with Cb = the molarity of NaOH = TO BE DETERMINED

⇒with Vb = the volume of NaOH = 0.0175 L

⇒with b = the coefficient of NaOH = 1

⇒with Ca = the molarity of HClO4 = 0.198 M

⇒with Va = the volume of HClO4 = 0.0152 L

Cb*0.0175 = 0.198 * 0.0152

Cb = 0.172 M

The molarity of sodium hydroxide solution is 0.172 M

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since electrons are negative the answer is neagtaive