Question

6. How much of 0.25 M KI solution, in liters, is required to completely precipitate all the Pb²+ in
0.125 L of 0.75 M Pb(NO3)2?
2 KI + Pb(NO3)2 → Pbl₂ + 2 KNO3
Please help me

Answer 1

For number 8:


If we write the equation of the reaction that will take place, it is:
2HNO₃ + Na₂CO₃ → 2NaNO₃ + H₂CO3

The molar ratio of 2HNO₃ : Na₂CO₃ = 1 : 2
Therefore, we can set up the equation:
M₁V₁ = 2M₂V₂
Where the left side of the equation has the molarity and volume of HNO₃ and the right side has the molarity and concentration of Na₂CO₃. Substituting:
M₁ = (2 x 0.108 x 35.7) / 25
M₁ = 0.308