A solid sample of Fe1OH23 is added to 0.500 L of 0.250 M
aqueous H2SO4. The solution that remains is still acidic. It
is then titrated with 0.500 M NaOH solution, and it takes
12.5 mL of the NaOH solution to reach the equivalence
point. What mass of Fe1OH23 was added to the H2SO4
solution?

Question

Accepted Answer

Hi everyone here we have a question telling us that a sample of calcium hydroxide was dissolved in 750 ml Of 0.500 molar hydrochloric acid solution. It was then tie traded with 15 ml of 0.25 Mueller potassium hydroxide solution. to reach the equivalence point, calculate the mass of calcium hydroxide. So our moles of hydroxide from calcium hydroxide plus the moles of hydroxide from potassium hydroxide equals the moles of hydrogen from hydrochloric acid. And that's because we are at our equivalence point. So that means two times the moles of calcium hydroxide plus the moles a potassium hydroxide equals the moles of hydrochloric acid. Now because polarity equals moles over leader, we can find our moles by multiplying our polarity times our leaders. So our moles of hydrochloric acid Is going to equal zero .50 Moller Times 0.750 l And that equals 0. moles of hydrochloric acid. Our moles of potassium hydroxide is going to equal 0.25 moller Times 0.015 l And that equals 0.0's zero 375 malls of potassium hydroxide. So going back to this equation here we can get to times the moles of calcium hydroxide equals the moles of hydrochloric acid minus the moles of potassium hydroxide and plugging in what we know two times the moles of calcium hydroxide equals 0. moles of hydrochloric acid zero 375 moles of potassium hydroxide and that means two times are moles of calcium hydroxide Equals 0. 7125 moles. And now we're going to provide both sides by two. So our moles of calcium hydroxide Equals 0.186 moles. So our molar mass of calcium hydroxide is 74.1 grams per mole. So our mass of calcium hydroxide Equals 0.186 moles times 74.1 g over one mole. And our moles are canceling out here And. 13 point 13. And that is our final answer. Thank you for watching. Bye.

A solid sample of Fe1OH23 is added to 0.500 L of 0.250 M aqueous H2SO4. The solution that remains is still acidic. It is then titrated with 0.500 M NaOH solution, and it takes 12.5 mL of the NaOH solution to reach the equivalence point. What mass of Fe1OH23 was added to the H2SO4 solution?

Verified Solution

Key Concepts

Stoichiometry

Titration

Molar Mass