Help me with this question please. For each of your reactions, use values from y
ID: 1036240 • Letter: H
Question
Help me with this question please.
For each of your reactions, use values from your textbook or the CRC handbook (the professor said to look this information in Google) to calculate what the values of Ka or Kb should have been for each of your salts. Compare these values to your experimental values. Where your values reasonably close? What errors might explain any discrepancies?
Table 2. Hydrolysis of Salts
# of equetion
0.10 M Solutions
Hydrolysis Ions
Spectator Ions
Ka
Kb
7.1
NaCl
-
Na+, Cl–
7.6 x 10^-13
0.0132
7.2
Na3C6H5O7
C6H5O73–
Na+
3.98 x 10^-5
2.51 x 10^-10
7.3
Na2CO3
CO32–
Na+
1.14 x 10^-10
8.97 x 10^-5
7.4
NH4Cl
NH4+
Cl–
9.5 x 10^-14
0.105
7.5
NaHSO4
-
Na+, SO42–
0.0104
1.32 x 10^-24
7.6
NH4C2H3O2
NH4+ , CH3–COO–
-
2 x 10^-13
5 x 10^-14
7.7
Na2SO3
SO32–
Na+
2.4 x 10^-7
4.2 x 10^-8
# of equetion
0.10 M Solutions
Hydrolysis Ions
Spectator Ions
Ka
Kb
7.1
NaCl
-
Na+, Cl–
7.6 x 10^-13
0.0132
7.2
Na3C6H5O7
C6H5O73–
Na+
3.98 x 10^-5
2.51 x 10^-10
7.3
Na2CO3
CO32–
Na+
1.14 x 10^-10
8.97 x 10^-5
7.4
NH4Cl
NH4+
Cl–
9.5 x 10^-14
0.105
7.5
NaHSO4
-
Na+, SO42–
0.0104
1.32 x 10^-24
7.6
NH4C2H3O2
NH4+ , CH3–COO–
-
2 x 10^-13
5 x 10^-14
7.7
Na2SO3
SO32–
Na+
2.4 x 10^-7
4.2 x 10^-8
Explanation / Answer
Salts
#7.1
NaCl : The Ka and Kb values are different from the literature values. The expected Ka = Kb = 1 x 10^-7.
The error could be due to incorrect measurement of amount of NaCl present in solution.
#7.2
Na3C6H5O7 : The Kb value is lower than the expected value.
The error could be due to insufficient hydrolysis of ion in solution.
#7.3
Na2CO3 : The Kb value is lower than the literature reported value.
The error could be due to incomplete hydrolysis of CO3^2- in solution.
#7.4
NH4Cl : The Ka value is far less than the expected literature value for NH4+
This could be due to higher amount of NH4Cl in solution which reduces ionization constant.
#7.5
NaHSO4 : The Kb value is much lower than expected.
The error could be due to HSO4- going to second ionization much readily than hydrolysis to H2SO4.
#7.6
NH4C2H3O2 : The Ka and Kb values are closer to the neutral pH
This is as per expectation.
#7.7
Na2SO3 : The Kb value is lower than expected literature value.
The error could be due to incomplete hydrolysis of SO3^2- in solution.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.