How many grams of CuOH2 will precipitate when excess KOH sol
How many grams of Cu(OH)2 will precipitate when excess KOH solution is added to 54.0 mL of 0.656 M Cu(NO3)2 solution?
b.  What volume of a 0.121 M nitric acid solution is required to neutralize 13.3 mL of a 0.164 M calcium hydroxide solution?
 
 mL nitric acid
Solution
Ans :
a) Number of moles of Cu(NO3)2 = 0.656 x 0.054 = 0.035424 mol
So the number of moles of Cu(OH)2 will be 0.035424 mol
Then the mass of compound precipitated = 0.035424 x molar mass
= 0.035424 x 97.561
= 3.456 grams
b) The reaction is given as :
2HNO3 + Ca(OH)2 = Ca(NO3)2 + 2H2O
Using the formula , M1 V1 / n1 = M2 V2 / n2
where M is molarity , V is volume and n is number of moles
(0.121 x V ) / 2 = 0.164 x 13.3
V = 36.05 mL nitric acid

