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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answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e