Calculate the volume of a 1.420 m naoh solution required to titrate 34.55 ml of a 1.500 m h3po4 solution.

109.5 mL.

How many moles of H₃PO₄ to neutralize?

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How many moles of NaOH are needed to neutralize that much H₃PO₄?

H₃PO₄ is inorganic. All three of its H atoms need to neutralized. It takes one OH⁻ to neutralize each H from H₃PO₄. Each formula unit of NaOH will supply one OH⁻ ion. Neutralizing each mole of H₃PO₄ will thus take three moles of NaOH.

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How many milliliters of NaOH?

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