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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n+h→nh3

we must remember that nitrogen and hydrogen are both diatomic molecules in their standard gas form. this adjusts the equation to

n2+h2→nh3

now we need to adjust coefficients in order to balance the atoms on each side of the equation. currently we have 2 atoms of nitrogen and 2 atoms of hydrogen on the reactant side and 1 atom of nitrogen and 3 atoms of hydrogen on the product side.

we can balance the hydrogens by placing a coefficient of 2 in front of ammonia and a coefficient of 3 in front of the hydrogen.

n2+3h2→2nh3

this gives us 6 hydrogen on each side and coincidentally the nitrogens now equal 2 on each side.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3