Question

Question 5: Aqueous barium hydroxide reacts with aqueous phosphoric acid in a neutralization reaction, which also produces a precipitate. [3.5pts for a; 3pts each for b&c Write a balanced equation (including states of matter) for this reaction including all reactants and products. a. If you react 25.0mL of 2.25M phosphoric acid, what mass (grams) of precipitate could be formed? b. If you react 25.0mL of 2.25M barium hydroxide, what mass (grams) of precipitate could be formed? c.

Answer 1

A) 3Ba(OH)₂(aq) + 2H ₃PO₄(aq) -> Ba ₃(PO ₄)₂(s) + 6H ₂O(l)

B) Moles of phosphoric acid = Molarity×volume/1000

= 2.25×25/1000 = 0.05625 moles

According to the reaction,

2 moles phosphoric acid give 601.93 g precipitate.

0.05625 moles phosphoric acid give 601.93×0.05625/2 g precipitate

= 16.93 g precipitate

C) Moles of barium hydroxide = 25×2.25/1000 = 0.05625

According to the reaction,

3 mole barium hydroxide give 601.93 g precipitate

0.05625 mole barium hydroxide give 601.93×0.05625/3 g

= 11.29 g