Jump to content

User:EagleFalconn/ThermoSandbox

From Wikipedia, the free encyclopedia

What do you think Peter?My comments are below.

Acids
Compound Equilibrium pKa ΔH0 /kJ mol-1 TΔS0 /kJ mol-1
HA = Acetic acid HA ⇌ H+ + A- 4.756 -0.41 26.73
H2A+ = GlycineH+ H2A+ ⇌ HA + H+ 2.351 4.00 17.41
HA ⇌ H+ + A- 9.78 44.20 100
H2A = Maleic acid H2A ⇌ HA- + H+ 1.92 1.10 12.1
HA- ⇌ H+ + A2- 6.27 -3.60 32.2
H3A = Citric acid H3A ⇌ H2A- + H+ 3.128 4.07 21.92
H2A- ⇌ HA2- + H+ 4.76 2.23 29.4
HA2- ⇌ A3- + H+ 6.40 -3.38 33.1
HA = Boric acid HA ⇌ H+ + A- 9.237 13.80 66.51
H3A = Phosphoric acid H3A ⇌ H2A- + H+ 2.148 -8.00 4.26
H2A- ⇌ HA2- + H+ 7.20 3.60 44.67
HA2- ⇌ A3- + H+ 12.35 16.00 86.47
HA- = Hydrogen sulphate HA- ⇌ A2- + H+ 1.99 -22.40 -11.1
H2A = Oxalic acid H2A ⇌ HA- + H+ 1.27 -3.90 3.35
HA- ⇌ A2- + H+ 4.266 7.00 17.34


Conjugate acid of bases
Compound Equilibrium pKa ΔH0 /kJ mol-1 TΔS0 /kJ mol-1
B = Ammonia HB+ ⇌ B + H+ 9.245 51.95 104.7
B = Methylamine HB+ ⇌ B + H+ 10.645 44.13 104.9
B= Triethylamine HB+ ⇌ B + H+ 10.72 43.13 104.3

pKa table

[edit]
Chemical Name Equilibrium pKa
Acetic acid [1] HA ⇌ H+ + A- 4.756
Adenine[1] HA ⇌ H+ + A- 4.17
Aniline [2] HA ⇌ H+ + A- 27
Arsenic acid [2] H3A ⇌ H2A- + H+ 2.22
H2A- ⇌ HA2- + H+ 6.98
HA2- ⇌ A3- + H+ 11.53
Benzoic acid[1] HA ⇌ H+ + A- 4.204
Boric acid [2] HA ⇌ H+ + A- 9.21
Butanoic acid [2] HA ⇌ H+ + A- 4.82
Chromic acid [2] H2A ⇌ HA- + H+ 0.98
HA- ⇌ A2- + H+ 6.5
Codeine [2] HA ⇌ H+ + A- 8.17
Cresol [2] HA ⇌ H+ + A- 10.29
Diethylene glycol [2] HA ⇌ H+ + A- 14.18
Formic acid[1] HA ⇌ H+ + A- 3.751
Glycerol [2] HA ⇌ H+ + A- 13.99
Hydrofluoric acid [2] HA ⇌ H+ + A- 3.17
Hydrocyanic acid [2] HA ⇌ H+ + A- 9.21
Hydrogen selenide [2] HA ⇌ H+ + A- 3.89
Hydrogen peroxide (90%) [2] HA ⇌ H+ + A- 11.7
Lactic acid [2] HA ⇌ H+ + A- 3.86
Maleic acid [2] H2A ⇌ HA- + H+ 1.92
HA- ⇌ A2- + H+ 6.23
Propanoic acid [2] HA ⇌ H+ + A- 4.87
Phenol[1] HA ⇌ H+ + A- 9.99
Phosphoric acid[3] H3A ⇌ H2A- + H+ 2.12
H2A- ⇌ HA2- + H+ 7.21
HA2- ⇌ A3- + H+ 12.38
L-(+)-Ascorbic Acid[1] H2A ⇌ HA- + H+ 4.17
HA- ⇌ A2- + H+ 11.57

Comments

[edit]

The IUPAC recommendation for a table of numbers is for each quantity heading to be "quantity/dimension"

T Delta S in the last column.

When quoting equilibrium constants the IUPAC recommendation in the Compendium of Analytical Nomenclature is to specify the equilibrium, as was done in the goldmine, Table 8. This eliminates any possible ambiguity. I hesitated to do that because I thought it would look messy, but it may be better after all. Here is my suggestion, in part:

Compound Equilibrium pKa ΔH0 /kJ mol-1 TΔS0 /kJ mol-1
AH3=Citric acid AH3 AH2 - + H+ 3.128 4.07 21.92
AH2- AH 2- + H+ 4.76 2.23 29.4
AH- A 3- + H+ 6.40 -3.38 33.1
B =ammonia BH+ B + H+ 9.245 51.95 104.7

The same treatment should be accorded to the table of pK values. Petergans (talk) 08:25, 2 August 2008 (UTC)

  1. ^ a b c d e f Speight, James G. Lange's Handbook of Chemistry (16th Edition). McGraw-Hill.
  2. ^ a b c d e f g h i j k l m n o p Knovel Critical Tables (2nd Edition). (2003). Knovel.
  3. ^ Brown, T.E. (2006). Chemistry The Central Science (10th ed.). Pearson Publications. pp. A27. ISBN 0131096869. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)