Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Using the given data and pH at the half equivalence point, what is the pKa and K

ID: 952954 • Letter: U

Question

Using the given data and pH at the half equivalence point, what is the pKa and Ka of the reaction between acetic acid and NaOH? I tried to attach the titration Curve but couldnt. sorry:(

please show all steps and units

Acetic acid (0.1 M) and NaOH (0.1 M) were used.

Volume of NaOH delivered to Acetic Acid

pH

1

3.39

2

3.6

3

3.84

4

4

5

4.2

6

4.36

7

4.4

8

4.45

9

4.58

10

4.75

11

4.67

12

4.78

13

4.8

14

5

15

5.03

15.5

5.03

16

5.07

16.5

5.1

17

5.13

17.5

5.16

18

5.16

18.5

5.19

19

5.24

19.5

5.28

20

5.33

20.5

5.39

21

5.46

21.5

5.46

22

5.54

22.5

5.62

23

5.72

23.5

5.87

24

5.99

24.5

6.35

25

6.8

25.5

10.61

26

11.2

27

10.48

28

11.88

29

12.01

30

12.08

Volume of NaOH delivered to Acetic Acid

pH

1

3.39

2

3.6

3

3.84

4

4

5

4.2

6

4.36

7

4.4

8

4.45

9

4.58

10

4.75

11

4.67

12

4.78

13

4.8

14

5

15

5.03

15.5

5.03

16

5.07

16.5

5.1

17

5.13

17.5

5.16

18

5.16

18.5

5.19

19

5.24

19.5

5.28

20

5.33

20.5

5.39

21

5.46

21.5

5.46

22

5.54

22.5

5.62

23

5.72

23.5

5.87

24

5.99

24.5

6.35

25

6.8

25.5

10.61

26

11.2

27

10.48

28

11.88

29

12.01

30

12.08

Explanation / Answer

form the data :

at 9 ml of NaOH ------------> pH = 4.58

at 10 ml of NaOH ------------> pH = 4.75

at 11 ml of NaOH ------------> pH = 4.67

at 12 ml of NaoH -------------> pH = 4.78

from these readings the changes statered at 10 mL NaOH so . it is half-equivalence point.

at half-equivalence point. pH = pka

pH = 4.75 = pKa

pKa = 4.75

Ka = 10^-pKa

Ka = 10^-4.75

Ka = 1.8 x 10^-5