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During a titration, 50.0 ml of 0.2M NaOH were required to neutralize 50.0ml of H3PO4. What's the concentration of the H3PO4 solution? Question 9 options: A) 0.07M B) 1.8M C) 0.6M D) 0.2M

User Qwetty
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2 Answers

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Answer:

A.) 0.07M

Step-by-step explanation:

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User Aaron Bertsch
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Answer:

0.07 M

Step-by-step explanation:

Given data:

Volume of NaOH = 50.0 mL

Molarity of NaOH = 0.2 M

Volume of H₃PO₄ = 50.0 mL

Concentration of H₃PO₄ = ?

Solution:

3NaOH + H₃PO₄ → Na₃PO₄ + 3H₂O

Number of moles of NaOH react:

Molarity = number of moles / volume in L

0.2 M = number of moles = 0.05 L

Number of moles = 0.01 mol

Now we will compare the moles of NaOH with H₃PO₄ .

NaOH : H₃PO₄

3 : 1

0.01 : 1/3×0.01 = 0.0033

Concentration of H₃PO₄:

Molarity = number of moles / volume in L

Molarity = 0.0033 mol / 0.05 L

Molarity = 0.07 M

User BassMHL
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