pKa values to know

Question 1

What is the pKa value of HI?

Answer 1

-10

Question 2

What is the pKa value of HBr?

Answer 2

-8

Question 3

What is the pKa value of HCl?

Answer 3

-7

Question 4

What is the pKa value of HF?

Answer 4

3

Question 5

What is the pKa value of an oxocarbenium ion (protonated carbonyl)?

Answer 5

-6 to -8

Question 6

What is the pKa value of an oxonium ion (protonated alcohol/ether)?

Answer 6

-2

Question 7

What is the pKa value of a hydronium ion (protonated water or an aqueous solution of any stronger acid)?

Answer 7

-2

Question 8

What is the pKa value of carboxylic acid? Or a pyridinium ion?

Answer 8

5

Question 9

What is the pKa value of phenol? Or an ammonium ion?

Answer 9

10

Question 10

What is the pKa value of a primary or secondary amide?

Answer 10

15

Question 11

What is the pKa value of water?

Answer 11

16

Question 12

What is the pKa value of alcohols?

Answer 12

16-18

Question 13

What is the pKa value of a-aldehyde, a-ketone?

Answer 13

20

Question 14

What is the pKa of a terminal alkyne?

Answer 14

25

Question 15

What is the pKa of an a-ester, a-amide?

Answer 15

25

Question 16

What is the pKa of hydrogen (H2)?

Answer 16

36

Question 17

What is the pKa of ammonia, primary amine, or secondary amine?

Answer 17

40

Question 18

What is the pKa of allylic/benzylic? (e.g., PhCH3)

Answer 18

41

Question 19

What is the pKa value of arene?

Answer 19

43

Question 20

What is the pKa of alkene/vinylic?

Answer 20

50

Question 21

What is the pKa value of alkane?

Answer 21

50+