I know most of them... If I cared enough maybe I would write a list... Wait, someone already have done that! Gotta find that thread!
Edit Tide: Found it, here:
1. H (Hyrogen) = Princess Hilda (II)
2. He (Helium) = Heidegger (VII)
3. Li (Lithium) = Lightning (XIII)
4. Be (Beryllium) = Black Belt (I)
5. B (Boron) = Bartz (V)
6. C (Carbon) = Cidolfus (XII) / Cyan (VI)
7. N (Nitrogen) = NORG (VIII)
8. O (Oxygen) = Odin (various)
9. F (Fluorine) = Fighter (I)
10. Ne (Neon) = Necron (IX)
11. Na (Sodium) = Nanaki [Red XIII] (VII)
12. Mg (Magnesium) = Mog (VI)
13. Al (Aluminum) = Prince Alus (III)
14. Si (Silicon) = Siren (various)
15. P (Phosphorus) = Propagator (VIII)
16. S (Sulfur) = Squall (VIII) / Shiva (various)
17. Cl (Chlorine) = Cloud (VII)
18. Ar (Argon) = Aria (III)
19. K (Potassium) = Kain (IV)
20. Ca (Calcium) = Cactuar (various)
21. Sc (Scandium) = Scarlet (VII)
22. Ti (Titanium) = Tidus (X)
23. V (Vanadium) = Vaan (XII)
24. Cr (Chromium) = Carbuncle (various)
25. Mn (Manganese) = Minwu (II)
26. Fe (Iron) = Freya (IX)
27. Co (Cobalt) = Chocobo (various)
28. Ni (Nickel) = Knights of the Round (VII)
29. Cu (Copper) = Kuja (IX)
30. Zn (Zinc) = Zidane (IX) / Xande (III)
31. Ga (Gallium) = Garnet (IX)
32. Ge (Germanium) = Gestahl (VI)
33. As (Arsenic) = Astos (I)
34. Se (Selenium) = Sephiroth (VII)
35. Br (Bromine) = Borghen (II)
36. Kr (Krypton) = Krile
37. Rb (Rubidium) = Ruby WEAPON (VII)
38. Sr (strontium) = Serah (III)
39. Y (Yttrium) = Yuna (X)
40. Zr (Zirconium) = Zeromus (IV)
41. Nb (Niobium) = Neo Bahamut (VII)
42. Mo (Molybdenum) = Mobile Type 8 (VIII)
43. Tc (Technetium) = Lenna Tycoon (V)
44. Ru (Ruthenium) = Rikku (X)
45. Rh (Rhodium) = Ricard Highwind (II)
46. Pd (Palladium) = Pandemona (VIII)
47. Ag (Silver) = Aerith Gainsborough (VII)
48. Cd (Cadmium) = Cloud of Darkness (III) / Cidolfus (XII)
49. In (Indium) = Ingus (III)
50. Sn (Tin) = Snow (XIII)
51. Sb (Antimony) = Sabin (VI)
52. Te (Tellurium) = Terrato [Midgardsormr] (various)
53. I (Iodine) = Ifrit (various)
54. Xe (Xenon) = Exdeath (V)
55. Cs (Caesium) = Caith Sith (VII)
56. Ba (Barium) = Barret (VII)
57. La (Lanthanum) = Leviathan (II)
58. Ce (Cerium) = Cecil (IV)
59. Pr (Praseodymium) = Promathia (XI)
60. Nd (Neodymium) = Alexander (various)
61. Pm (Promethium) = Porom (IV)
62. Sm (Samarium) = Seymour (X)
63. Eu (Europium) = Yuffie (VII)
64. Gd (Gadolinium) = Garland (I)
65. Tb (Terbium) = Terra Branford (VI)
66. Dy (Dysprosium) = Rydia (IV)
67. Ho (Holium) = Hojo (VII)
68. Er (Erbium) = Edgar Roni Figaro (VI)
69. Tm (Thullium) = Tiamat (various)
70. Yb (Ytterbium) = Yojimbo (X)
71. Lu (Lutetium) = Lulu (X)
72. Hf (Hafnium) = Josef (II)
73. Ta (Lutetium) = Tellah (IV) / Tifa Lockhart (VII)
74. W (Tungsten) = White Mage (I)
75. Re (Rhenium) = Relm (VI)
76. Os (Osmium) = Chaos (I)
77. Ir (Iridium) = Irvine (VIII)
78. Pt (Platinum) = Prince Trion (XI)
79. Au (Gold) = Auron (X)
80. Hg (Mercury) = Galuf H. Baldesion (V)
81. Tl (Thallium) = Tifa Lockhart (VII) / Tellah (IV)
82. Pb (Lead) = Puck of Burmecia (IX)
83. Bi (Bismuth) = Biran Ronso (X)
84. Po (Polonium) = Penelo (XII)
85. At (Astatine) = Atomos (IX)
86. Rn (Radon) = Reno (VII)
87. Fr (Francium) = Firion (II)
88. Ra (Radium) = Ramuh (various)
89. Ac (Actinium) = Arc (III)
90. Th (Thorium) = Thief (I)
91. Pa (Protactinium) = Palom (IV)
92. U (Uranium) = Unei (III)
93. Np (Neptunium) = Phoenix (V)
94. Pu (Plutonium) = PuPu (VIII)
95. Am (Americium) = Amarant Coral (IX)
96. Cm (Curium) = Edward Chris von Muir (IV)
97. Bk (Berkelium) = Black Mage (I)
98. Cf (Californium) = Kefka [Cefca] (VI)
99. Es (Einsteinium = Celes Chere (VI)
100. Fm (Fermium) = Fran (XII)
101. Md (Mendelevium) = Mid (V)
102. No (Nobelium) = Gabranth [Noah] (XII)
103. Lr (Lawrencium) = Laguna Loire (VIII)
104. Rf (Rutherfodium) = Refia (III)
105. Db (Dubnium) = Diabolos (various)
106. Sg (Seaborgium) = Setzer Gabbiani (VI)
107. Bh (Bohrium) = Bahamut (I)
108. Hs (Hassium) = Hades (VII)
109. Mt (Metnerium) = Matoya (I)
110. Ds (Darmstadtium) = Desch (III)
111. Rg (Roentgenium) = Red Mage (I)
112. Uub (Ununbium) = Rubicant (IV)
113. Uut (Ununtrium) = Ultimecia (VIII)
114. Uuq (Ununquadium) = Unicorn (various)
115. Uut (Ununpentium) = Ultima Weapon (various)
116. UUh (Ununhexium) = Ultima (XII)
117. Uus (Ununseptium) = Ultros (VI)
118. Uuo (Ununoctium) = Umaro (VI)
This is copied from the site the picture came from!!! The things that may be wrong is not my fault! I'm far more perfect to make an error when it comes to final fantasy.