Question

Given that a 1.00-g sample of piperazine hexahydrate is dissolved in enough water to produce 100.0 mL of solution and is titrated with 0.500 M HCl, what is the volume of HCl in mL at

-the initial pH of the solution (pH = 11.23)

-the pH at the 25%-neutralization point of the first neutralization (10.26)

-the pH at the 50%-neutralization point of the first neutralization (9.78)

-the pH at the 75%-neutralization point of the first neutralization (9.30)

-the pH at the first equivalence point (7.56)

-the pH at the 25%-neutralization point of the second neutralization (5.81)

-the pH at the 50%-neutralization point of the second neutralization (5.33)

-the pH at the 75%-neutralization point of the second neutralization (4.85)

-the pH at the second equivalence point (3.35) T

his is for Piperazine, HN(C4H8)NH, which is a diprotic weak base used as a corrosion inhibitor and an insecticide and has the following properties: pKb1=4.22pKb2=8.67 For writing the reactions of this base in water, it can be helpful to abbreviate the formula as Pip: Pip+H2O Piperazine, HN(C4H8)NH, is a diprotic weak base used as a corrosion inhibitor and an insecticide and has the following properties: pKb1=4.22pKb2=8.67 For writing the reactions of this base in water, it can be helpful to abbreviate the formula as Pip: Pip+H2O ⇌ PipH+ + H2O

PipH+ + OH− ⇌ PipH22+ + OH−

The piperazine used commercially is a hexahydrate with the formula C4H10N2⋅6H2O

Answer 1

The molecular weight of piperazine hexahydrate

1.00-g sample of piperazine hexahydrate corresponds to

Convert the unit from mole to mmol

The volume of HCl in mL at -the initial pH of the solution (pH = 11.23) is 0 ml.

The volume of HCl in mL at-the pH at the 25%-neutralization point of the first neutralization (10.26) is

The volume of HCl in mL at -the pH at the 50%-neutralization point of the first neutralization (9.78) is

The volume of HCl in mL at -the pH at the 75%-neutralization point of the first neutralization (9.30) is

The volume of HCl in mL at -the pH at the first equivalence point (7.56) is

The volume of HCl in mL at -the pH at the 25%-neutralization point of the second neutralization (5.81)

The volume of HCl in mL at -the pH at the 50%-neutralization point of the second neutralization (5.33)

The volume of HCl in mL at -the pH at the 75%-neutralization point of the second neutralization (4.85)

The volume of HCl in mL at -the pH at the second equivalence point (3.35) T